Add Revit Dynamo diagnostic scripts

compose.yaml overrode the image's own entrypoint to start "tsx watch" and
"next dev" with CHOKIDAR_USEPOLLING and WATCHPACK_POLLING enabled. The
built dist/ and .next from the image were never used, and the polling
watchers kept both containers busy around the clock whether or not
anyone used the application.

Split the two use cases: compose.yaml now runs node dist/server/index.js
and next start with no source mounts and no watchers, and the watching
setup moves to compose.dev.yaml.

next build writes the rewrite destinations from next.config.mjs into
.next/routes-manifest.json, so next start cannot pick up API_INTERNAL_URL
at runtime the way next dev does. Pass it as a build argument.

Give the web container its own probe. The healthcheck hit "/", which
redirects to "/projects", and fetch follows redirects, so every probe
rendered two pages every five seconds. "/health" could not serve as the
probe because next.config.mjs rewrites it to the API. Add "/web-health"
as a route handler, exclude it from the proxy matcher, and relax both
intervals to 30s.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

.gitignore

@@ -4,3 +4,4 @@ dist/
 data/*.db
 data/backups/*.db
 .codex/*.log
+dynamo/output/

Dockerfile

@@ -1,10 +1,17 @@
-FROM node:22
+FROM node:24
 WORKDIR /app
 
 COPY package*.json ./
 RUN npm ci
 
 COPY . .
+
+# next build writes the rewrite destinations from next.config.mjs into
+# .next/routes-manifest.json, so "next start" cannot pick up a different
+# API URL later. The value has to be known here, not just at runtime.
+ARG API_INTERNAL_URL=http://localhost:3000
+ENV API_INTERNAL_URL=$API_INTERNAL_URL
+
 RUN npm run build:api && npm run build:web
 
 RUN mkdir -p data && chmod +x scripts/docker-start.sh

README.md

@@ -62,15 +62,29 @@ docker compose logs --follow
 docker compose down
 ```
 
-Der Compose-Stack startet Entwicklungsserver mit Quellcode-Mounts. Er ist kein
-Produktionsdeployment. Details stehen in
+`compose.yaml` startet den Produktionsstand: gebautes `dist/` und `next start`,
+ohne Quellcode-Mounts und ohne Datei-Watcher. Details stehen in
 [Deployment und Betrieb](docs/deployment.md).
 
+Für die Entwicklung mit Hot Reload gibt es einen eigenen Stack mit
+Quellcode-Mounts und Watchern:
+
+```powershell
+docker compose -f compose.dev.yaml up --build --detach
+docker compose -f compose.dev.yaml logs --follow
+docker compose -f compose.dev.yaml down
+```
+
+Die Watcher darin laufen im Polling-Modus, weil Bind-Mounts unter Windows und
+macOS keine inotify-Events durchreichen. Das kostet dauerhaft CPU, auch wenn
+niemand die Anwendung benutzt — deshalb gehört dieser Stack nicht auf einen
+Server.
+
 ## Direkte lokale Entwicklung
 
 Voraussetzungen:
 
-- Node.js 22
+- Node.js 24
 - npm
 
 ```powershell

compose.dev.yaml

@@ -0,0 +1,87 @@
+# Development stack: source mounts, watching dev servers, hot reload.
+#   docker compose -f compose.dev.yaml up --build
+#
+# The polling watchers below are needed for bind mounts on Windows and
+# macOS, where inotify events do not cross the VM boundary. They cost
+# continuous CPU, which is why the production stack in compose.yaml does
+# not run watchers at all.
+name: leistungsbilanz-dev
+
+x-logging: &logging
+  driver: json-file
+  options:
+    max-size: "20m"
+    max-file: "10"
+
+services:
+  api:
+    build:
+      context: .
+    command:
+      - sh
+      - -c
+      - npm run db:migrate && npm run db:verify:circuit-schema && npm run dev:api
+    environment:
+      PORT: "3000"
+      CHOKIDAR_USEPOLLING: "true"
+      LOG_LEVEL: "${LOG_LEVEL:-debug}"
+    init: true
+    restart: unless-stopped
+    logging: *logging
+    ports:
+      - "3000:3000"
+    volumes:
+      - ./src:/app/src
+      - ./scripts:/app/scripts
+      - ./data:/app/data
+      - ./drizzle.config.ts:/app/drizzle.config.ts:ro
+      - ./tsconfig.json:/app/tsconfig.json:ro
+    healthcheck:
+      test:
+        - CMD
+        - node
+        - -e
+        - fetch('http://localhost:3000/health').then(response=>{if(!response.ok)process.exit(1)}).catch(()=>process.exit(1))
+      interval: 30s
+      timeout: 3s
+      retries: 5
+      start_period: 20s
+
+  web:
+    build:
+      context: .
+    command:
+      - npm
+      - run
+      - dev:web
+      - --
+      - --hostname
+      - 0.0.0.0
+    environment:
+      API_INTERNAL_URL: http://api:3000
+      WATCHPACK_POLLING: "true"
+      NEXT_TELEMETRY_DISABLED: "1"
+      LOG_LEVEL: "${LOG_LEVEL:-debug}"
+    init: true
+    restart: unless-stopped
+    logging: *logging
+    depends_on:
+      api:
+        condition: service_healthy
+    ports:
+      - "3001:3001"
+    volumes:
+      - ./src:/app/src
+      - ./next.config.mjs:/app/next.config.mjs:ro
+      - ./tsconfig.json:/app/tsconfig.json:ro
+      - ./tsconfig.next.json:/app/tsconfig.next.json:ro
+    healthcheck:
+      test:
+        - CMD
+        - node
+        - -e
+        - fetch('http://localhost:3001/web-health').then(response=>{if(!response.ok)process.exit(1)}).catch(()=>process.exit(1))
+      interval: 30s
+      timeout: 3s
+      retries: 5
+      start_period: 20s

compose.yaml

@@ -1,68 +1,73 @@
 name: leistungsbilanz
 
+x-build: &build
+  context: .
+  args:
+    # Baked into .next/routes-manifest.json by next build; see Dockerfile.
+    API_INTERNAL_URL: http://api:3000
+
+x-logging: &logging
+  driver: json-file
+  options:
+    max-size: "20m"
+    max-file: "10"
+
 services:
   api:
-    build:
-      context: .
+    build: *build
     command:
       - sh
       - -c
-      - npm run db:migrate && npm run db:verify:circuit-schema && npm run dev:api
+      - node scripts/run-migrations.js && node scripts/db-verify-circuit-schema.js && node dist/server/index.js
     environment:
+      NODE_ENV: production
       PORT: "3000"
-      CHOKIDAR_USEPOLLING: "true"
+      LOG_LEVEL: "${LOG_LEVEL:-info}"
     init: true
+    restart: unless-stopped
+    logging: *logging
     ports:
       - "3000:3000"
     volumes:
-      - ./src:/app/src
-      - ./scripts:/app/scripts
       - ./data:/app/data
-      - ./drizzle.config.ts:/app/drizzle.config.ts:ro
-      - ./tsconfig.json:/app/tsconfig.json:ro
     healthcheck:
       test:
         - CMD
         - node
         - -e
         - fetch('http://localhost:3000/health').then(response=>{if(!response.ok)process.exit(1)}).catch(()=>process.exit(1))
-      interval: 5s
+      interval: 30s
       timeout: 3s
-      retries: 12
+      retries: 5
       start_period: 20s
 
   web:
-    build:
-      context: .
+    build: *build
     command:
-      - npm
-      - run
-      - dev:web
-      - --
-      - --hostname
-      - 0.0.0.0
+      - node_modules/.bin/next
+      - start
+      - -p
+      - "3001"
     environment:
+      NODE_ENV: production
       API_INTERNAL_URL: http://api:3000
-      WATCHPACK_POLLING: "true"
       NEXT_TELEMETRY_DISABLED: "1"
+      LOG_LEVEL: "${LOG_LEVEL:-info}"
     init: true
+    restart: unless-stopped
+    logging: *logging
     depends_on:
       api:
         condition: service_healthy
     ports:
       - "3001:3001"
-    volumes:
-      - ./src:/app/src
-      - ./next.config.mjs:/app/next.config.mjs:ro
-      - ./tsconfig.json:/app/tsconfig.json:ro
-      - ./tsconfig.next.json:/app/tsconfig.next.json:ro
     healthcheck:
       test:
         - CMD
         - node
         - -e
-        - fetch('http://localhost:3001/').then(response=>{if(!response.ok)process.exit(1)}).catch(()=>process.exit(1))
-      interval: 5s
+        - fetch('http://localhost:3001/web-health').then(response=>{if(!response.ok)process.exit(1)}).catch(()=>process.exit(1))
+      interval: 30s
       timeout: 3s
-      retries: 12
+      retries: 5
       start_period: 20s

docs/circuit-list-editor-api.md

@@ -359,8 +359,9 @@ Response sketch:
 
 ### Circuit Structure
 
-- `GET /circuit-sections/:sectionId/next-identifier`
+- `GET /projects/:projectId/circuit-sections/:sectionId/next-identifier`
   - preview next identifier for section (`prefix + maxSuffix + 1`)
+  - returns 404 if the section does not belong to the given project
 
 Circuit and device-row field updates, standalone insertions/deletions, single
 or bulk device-row moves, circuit reorders and explicit renumbering are

docs/current-architecture.md

@@ -476,16 +476,28 @@ Kopieren in ein Projekt erzeugt ein eigenständiges Projektgerät.
   und Verteilerkomponenten. Separate
   1:1-Tabellen halten Stromkreis- und Komponenten-Schutzgeräte. Die früheren
   flachen Stromkreis-Schutzfelder sind aus der Baseline entfernt.
-  Ein triggergeführtes Register erzwingt bereits eine normalisierte,
+  Ein triggergeführtes Register erzwingt eine normalisierte,
   stromkreislistenweite BMK-Eindeutigkeit über Stromkreise und
-  Verteilerkomponenten. Snapshot- und Transfer-Integration verwenden aktuell
-  Snapshot-Schema 5. Persistente Insert/Delete/Update-Commands für
-  veränderliche Verteilerkomponenten, Gruppen einschließlich befüllter
-  Unterbäume sowie vollständige Gruppensortierung sind integriert. Der Editor
-  zeigt die geschützte Struktur an und bearbeitet veränderliche Gruppen- und
-  Fußkomponenten über dedizierte Command-Modale. Gruppenanlage, -umbenennung,
-  -sortierung, explizite Neunummerierung, Same-Category-Stromkreiswechsel,
-  geschütztes Unterbaumlöschen und Stromkreisschutz sind integriert.
+  Verteilerkomponenten. Der DB-Index normalisiert dabei nur über SQLites
+  eingebautes `lower()` (rein ASCII), erkennt also z.B. `"Ä1"` und `"ä1"` nicht
+  als denselben Wert. Die gemeinsame Prüfung
+  `src/db/repositories/equipment-identifier-uniqueness.persistence.ts`
+  schließt diese Lücke: Sie normalisiert mit JavaScripts Unicode-fähigem
+  `toLowerCase()` gegen das vollständige Register der Stromkreisliste und wird
+  von jedem Anlage-/Umbenennungspfad für Stromkreise und Verteilerkomponenten
+  aufgerufen, auch dort, wo zuvor kein Vorab-Check existierte. Snapshot- und
+  Transfer-Integration verwenden aktuell Snapshot-Schema 5. Persistente
+  Insert/Delete/Update-Commands für veränderliche Verteilerkomponenten,
+  Gruppen einschließlich befüllter Unterbäume sowie vollständige
+  Gruppensortierung sind integriert. Der Editor zeigt die geschützte Struktur
+  an und bearbeitet veränderliche Gruppen- und Fußkomponenten über dedizierte
+  Command-Modale. Gruppenanlage, -umbenennung, -sortierung, explizite
+  Neunummerierung, Same-Category-Stromkreiswechsel, geschütztes
+  Unterbaumlöschen und Stromkreisschutz sind integriert.
+  Migration `0006` ergänzt additiv Indizes auf `circuits.section_id` und
+  `circuit_device_rows.circuit_id`, den beiden am häufigsten gefilterten
+  Fremdschlüsselspalten sowie den Cascade-Delete-Pfaden von Abschnitten und
+  Stromkreisen.
 
 PostgreSQL ist bewusst nicht implementiert. Die Domainregeln und
 Transaktionsgrenzen sollen portabel bleiben; Schema und Betriebsmodell benötigen

docs/deployment.md

@@ -2,19 +2,27 @@
 
 ## Aktueller Status
 
-Es gibt derzeit kein unterstütztes Produktionsdeployment.
+Es gibt zwei Compose-Stacks.
 
-`compose.yaml` ist ausschließlich für lokale Entwicklung vorgesehen. Es startet
-`tsx watch` und `next dev`, bindet Quellcode vom Host ein und enthält weder TLS,
-Authentifizierung, Reverse Proxy, Prozesshärtung noch ein zentral betriebenes
-Datenbanksystem. Der Stack darf deshalb nicht als produktionsreif bezeichnet oder
-öffentlich erreichbar gemacht werden.
+`compose.yaml` startet den gebauten Stand: `node dist/server/index.js` und
+`next start`, ohne Quellcode-Mounts und ohne Datei-Watcher. Das ist der Stack
+für einen Server.
 
-## Entwicklungs-Topologie
+`compose.dev.yaml` startet `tsx watch` und `next dev` und bindet Quellcode vom
+Host ein. Die Watcher laufen im Polling-Modus, weil Bind-Mounts unter Windows
+und macOS keine inotify-Events durchreichen; das kostet dauerhaft CPU, auch
+ohne Benutzeraktivität. Dieser Stack gehört deshalb nur auf einen
+Entwicklungsrechner.
+
+Beides enthält weder TLS, Authentifizierung, Reverse Proxy, Prozesshärtung noch
+ein zentral betriebenes Datenbanksystem. Der Stack darf deshalb nicht öffentlich
+erreichbar gemacht werden.
+
+## Topologie
 
 | Komponente | Port | Healthcheck | Persistenz |
 | --- | ---: | --- | --- |
-| Next.js Web | 3001 | `GET /` | keine |
+| Next.js Web | 3001 | `GET /web-health` | keine |
 | Express API | 3000 | `GET /health` | `./data:/app/data` |
 | SQLite | Datei | Integritäts-/FK-Prüfung via Backup und Skript | `data/leistungsbilanz.db` |
 
@@ -24,11 +32,56 @@ Verwendete Umgebungsvariablen:
 - `API_INTERNAL_URL` – internes API-Ziel des Next.js-Rewrites, im Compose-Netz
   `http://api:3000`
 - `NEXT_TELEMETRY_DISABLED=1`
-- `CHOKIDAR_USEPOLLING=true` und `WATCHPACK_POLLING=true` für lokale
-  Dateibeobachtung in Docker
+- `CHOKIDAR_USEPOLLING=true` und `WATCHPACK_POLLING=true` – nur in
+  `compose.dev.yaml`, für Dateibeobachtung über Bind-Mounts hinweg
+- `LOG_LEVEL` – steuert für beide Dienste die Ausgabestufe des strukturierten
+  JSON-Loggers (`error`, `warn`, `info`, `verbose`, `debug`), Standard `info`.
+  Setzbar über eine `.env`-Datei neben `compose.yaml` oder
+  `LOG_LEVEL=verbose docker compose up`.
 
-Beim API-Start laufen zuerst `npm run db:migrate` und
-`npm run db:verify:circuit-schema`.
+Beim API-Start laufen zuerst die Migrationen und die Schemaprüfung
+(`scripts/run-migrations.js` und `scripts/db-verify-circuit-schema.js`, im
+Entwicklungsstack über `npm run db:migrate` und
+`npm run db:verify:circuit-schema`).
+
+`API_INTERNAL_URL` wirkt für `next start` zur **Build-Zeit**: `next build`
+schreibt die Rewrite-Ziele aus `next.config.mjs` fest in
+`.next/routes-manifest.json`. `compose.yaml` reicht den Wert deshalb als
+Build-Argument an das Image durch, nicht nur als Laufzeit-Variable.
+
+## Logging
+
+Beide Dienste schreiben strukturierte, einzeilige JSON-Log-Zeilen nach
+stdout/stderr (`docker compose logs --follow`). Jede Zeile enthält
+`timestamp`, `level`, `scope` und `message`. `compose.yaml` konfiguriert für
+beide Dienste den `json-file`-Treiber mit Rotation (`max-size: 20m`,
+`max-file: 10`, also bis zu 200 MB je Dienst); ohne diese Einstellung würde
+Docker mit der Standardkonfiguration unbegrenzt in eine einzelne Datei unter
+`/var/lib/docker/containers/<container-id>/` schreiben. Die Logs überleben
+einen Container-Neustart (`docker compose restart`), aber nicht das Entfernen
+des Containers (`docker compose down` gefolgt von `up` erzeugt neue
+Container und damit neue, leere Logdateien); für ein echtes Langzeitarchiv
+über Rebuilds hinweg müssten die Zeilen zusätzlich in eine Datei im
+gemounteten `./data`-Verzeichnis oder an ein externes Log-System geschrieben
+werden. Die Express-API protokolliert
+jede abgeschlossene Anfrage (Methode, Pfad, Status, Dauer; `/health` wird
+nicht mitgeloggt) sowie unbehandelte Exceptions/Promise-Rejections. Das
+Next.js-Frontend protokolliert Seitenanfragen (Navigation) über
+`src/proxy.ts` und unbehandelte Fehler über `src/instrumentation.ts`.
+Beide Prozesse schreiben zusätzlich alle fünf Minuten einen `verbose`-Heartbeat
+mit Laufzeit und Speicherverbrauch – nützlich, um Speicherlecks oder Hänger vor
+einem 502 über einen längeren Zeitraum nachzuvollziehen. Für die Detailsuche
+`LOG_LEVEL=debug` setzen; das protokolliert zusätzlich den Start jeder
+API-Anfrage und macht damit hängende (nie abgeschlossene) Requests sichtbar.
+Ein `close`-Ereignis ohne vorheriges `finish` wird als `request aborted before
+response finished` (`warn`) geloggt und zeigt damit vom Client oder einem
+vorgeschalteten Proxy abgebrochene Verbindungen.
+
+Eine unbehandelte Exception oder Promise-Rejection wird geloggt und beendet
+den jeweiligen Prozess anschließend bewusst (`process.exit(1)`), statt in
+einem unbekannten Zustand weiterzulaufen. Beide Dienste laufen deshalb mit
+`restart: unless-stopped`, damit Docker sie danach automatisch neu startet;
+ohne diese Policy würde ein Crash den Dienst dauerhaft unerreichbar lassen.
 
 ## Voraussetzungen für ein späteres Produktionssetup
 

dynamo/01_check_model_identity.py

@@ -0,0 +1,385 @@
+"""Read-only Revit 2026 model-identity diagnostics for a Dynamo Python node.
+
+Optional Dynamo input:
+    IN[0]: output directory or complete .json file path
+
+The script intentionally performs no Revit transaction and changes no model
+data. OUT contains a compact summary plus the complete report.
+"""
+
+import datetime
+import json
+import os
+import platform
+import sys
+import tempfile
+import traceback
+
+import clr
+
+clr.AddReference("RevitAPI")
+clr.AddReference("RevitServices")
+
+from Autodesk.Revit.DB import ModelPathUtils, StorageType  # noqa: E402
+from RevitServices.Persistence import DocumentManager  # noqa: E402
+
+
+CHECKED_PARAMETER_NAMES = ("LB_ModelId", "LB_ProjectId")
+
+
+def safe_text(value):
+    if value is None:
+        return None
+    try:
+        return str(value)
+    except Exception:
+        return None
+
+
+def element_id_text(element_id):
+    if element_id is None:
+        return None
+    try:
+        return str(element_id.Value)
+    except Exception:
+        try:
+            return str(element_id.IntegerValue)
+        except Exception:
+            return safe_text(element_id)
+
+
+def forge_type_id_text(value):
+    if value is None:
+        return None
+    try:
+        return value.TypeId
+    except Exception:
+        return safe_text(value)
+
+
+def parameter_value(parameter):
+    result = {
+        "hasValue": False,
+        "raw": None,
+        "display": None,
+    }
+    try:
+        result["hasValue"] = bool(parameter.HasValue)
+    except Exception:
+        pass
+
+    try:
+        storage_type = parameter.StorageType
+        if storage_type == StorageType.String:
+            result["raw"] = parameter.AsString()
+        elif storage_type == StorageType.Integer:
+            result["raw"] = int(parameter.AsInteger())
+        elif storage_type == StorageType.Double:
+            result["raw"] = float(parameter.AsDouble())
+        elif storage_type == StorageType.ElementId:
+            result["raw"] = element_id_text(parameter.AsElementId())
+    except Exception as error:
+        result["readError"] = safe_text(error)
+
+    try:
+        result["display"] = parameter.AsValueString()
+    except Exception:
+        pass
+    return result
+
+
+def describe_parameter(parameter):
+    definition = None
+    try:
+        definition = parameter.Definition
+    except Exception:
+        pass
+
+    name = None
+    if definition is not None:
+        try:
+            name = definition.Name
+        except Exception:
+            pass
+
+    is_shared = False
+    try:
+        is_shared = bool(parameter.IsShared)
+    except Exception:
+        pass
+
+    shared_guid = None
+    if is_shared:
+        try:
+            shared_guid = str(parameter.GUID)
+        except Exception:
+            pass
+
+    data_type = None
+    group_type = None
+    if definition is not None:
+        try:
+            data_type = forge_type_id_text(definition.GetDataType())
+        except Exception:
+            pass
+        try:
+            group_type = forge_type_id_text(definition.GetGroupTypeId())
+        except Exception:
+            pass
+
+    unit_type = None
+    try:
+        unit_type = forge_type_id_text(parameter.GetUnitTypeId())
+    except Exception:
+        pass
+
+    try:
+        storage_type = str(parameter.StorageType)
+    except Exception:
+        storage_type = None
+
+    try:
+        is_read_only = bool(parameter.IsReadOnly)
+    except Exception:
+        is_read_only = None
+
+    try:
+        user_modifiable = bool(parameter.UserModifiable)
+    except Exception:
+        user_modifiable = None
+
+    return {
+        "name": name,
+        "parameterId": element_id_text(getattr(parameter, "Id", None)),
+        "isShared": is_shared,
+        "sharedGuid": shared_guid,
+        "storageType": storage_type,
+        "dataTypeId": data_type,
+        "groupTypeId": group_type,
+        "unitTypeId": unit_type,
+        "isReadOnly": is_read_only,
+        "userModifiable": user_modifiable,
+        "value": parameter_value(parameter),
+    }
+
+
+def sorted_parameters(element):
+    parameters = []
+    try:
+        parameters = [describe_parameter(parameter) for parameter in element.Parameters]
+    except Exception:
+        return []
+    return sorted(
+        parameters,
+        key=lambda parameter: (
+            (parameter.get("name") or "").casefold(),
+            parameter.get("parameterId") or "",
+        ),
+    )
+
+
+def named_parameter_occurrences(element, parameter_name):
+    result = []
+    try:
+        parameters = element.GetParameters(parameter_name)
+        if parameters is not None:
+            result = [describe_parameter(parameter) for parameter in parameters]
+    except Exception:
+        parameter = None
+        try:
+            parameter = element.LookupParameter(parameter_name)
+        except Exception:
+            pass
+        if parameter is not None:
+            result = [describe_parameter(parameter)]
+    return result
+
+
+def loaded_assembly_versions():
+    result = {}
+    try:
+        from System import AppDomain
+
+        for assembly in AppDomain.CurrentDomain.GetAssemblies():
+            try:
+                name = assembly.GetName()
+                simple_name = str(name.Name)
+                if simple_name in (
+                    "DynamoCore",
+                    "DynamoCoreWpf",
+                    "DynamoRevitDS",
+                    "RevitAPI",
+                    "RevitServices",
+                ):
+                    result[simple_name] = str(name.Version)
+            except Exception:
+                continue
+    except Exception:
+        pass
+    return dict(sorted(result.items()))
+
+
+def get_cloud_identity(document):
+    result = {"isModelInCloud": False}
+    try:
+        result["isModelInCloud"] = bool(document.IsModelInCloud)
+    except Exception:
+        return result
+    if not result["isModelInCloud"]:
+        return result
+
+    try:
+        model_path = document.GetCloudModelPath()
+        result["userVisiblePath"] = ModelPathUtils.ConvertModelPathToUserVisiblePath(
+            model_path
+        )
+        for property_name, output_name in (
+            ("GetProjectGUID", "projectGuid"),
+            ("GetModelGUID", "modelGuid"),
+        ):
+            try:
+                result[output_name] = str(getattr(model_path, property_name)())
+            except Exception:
+                pass
+    except Exception as error:
+        result["readError"] = safe_text(error)
+    return result
+
+
+def get_worksharing_identity(document):
+    result = {"isWorkshared": False}
+    try:
+        result["isWorkshared"] = bool(document.IsWorkshared)
+    except Exception:
+        return result
+    if not result["isWorkshared"]:
+        return result
+
+    try:
+        model_path = document.GetWorksharingCentralModelPath()
+        result["centralModelPath"] = ModelPathUtils.ConvertModelPathToUserVisiblePath(
+            model_path
+        )
+    except Exception as error:
+        result["readError"] = safe_text(error)
+    return result
+
+
+def resolve_output_path(configured_path, report_name):
+    timestamp = datetime.datetime.now().strftime("%Y%m%d-%H%M%S")
+    default_directory = os.path.join(tempfile.gettempdir(), "leistungsbilanz-dynamo")
+    raw_path = safe_text(configured_path)
+    if raw_path is None or not raw_path.strip():
+        directory = default_directory
+        file_path = os.path.join(directory, report_name + "-" + timestamp + ".json")
+    else:
+        expanded = os.path.abspath(os.path.expandvars(os.path.expanduser(raw_path.strip())))
+        if expanded.lower().endswith(".json"):
+            file_path = expanded
+            directory = os.path.dirname(file_path)
+        else:
+            directory = expanded
+            file_path = os.path.join(directory, report_name + "-" + timestamp + ".json")
+    if not directory:
+        directory = os.getcwd()
+    if not os.path.isdir(directory):
+        os.makedirs(directory)
+    return file_path
+
+
+def write_json(file_path, payload):
+    temporary_path = file_path + ".tmp"
+    with open(temporary_path, "w", encoding="utf-8", newline="\n") as output:
+        json.dump(payload, output, ensure_ascii=False, indent=2, sort_keys=True)
+        output.write("\n")
+    os.replace(temporary_path, file_path)
+
+
+def get_input(index, default=None):
+    values = globals().get("IN", [])
+    try:
+        value = values[index]
+        return default if value is None else value
+    except Exception:
+        return default
+
+
+def build_report():
+    document = DocumentManager.Instance.CurrentDBDocument
+    if document is None:
+        raise RuntimeError("No active Revit document is available.")
+
+    project_information = document.ProjectInformation
+    if project_information is None:
+        raise RuntimeError("The active document has no Project Information element.")
+
+    application = document.Application
+    checked_parameters = {
+        name: named_parameter_occurrences(project_information, name)
+        for name in CHECKED_PARAMETER_NAMES
+    }
+    warnings = []
+    for name in CHECKED_PARAMETER_NAMES:
+        occurrences = checked_parameters[name]
+        populated = [
+            parameter
+            for parameter in occurrences
+            if parameter.get("value", {}).get("raw") not in (None, "")
+        ]
+        if not occurrences:
+            warnings.append(name + " is not bound to Project Information.")
+        elif not populated:
+            warnings.append(name + " exists but has no value on Project Information.")
+        elif len(occurrences) > 1:
+            warnings.append(name + " occurs more than once; use a shared-parameter GUID later.")
+
+    return {
+        "reportSchemaVersion": 1,
+        "generatedAt": datetime.datetime.now(datetime.timezone.utc).isoformat(),
+        "readOnly": True,
+        "environment": {
+            "revitVersionNumber": safe_text(getattr(application, "VersionNumber", None)),
+            "revitVersionName": safe_text(getattr(application, "VersionName", None)),
+            "revitSubVersionNumber": safe_text(
+                getattr(application, "SubVersionNumber", None)
+            ),
+            "pythonImplementation": safe_text(getattr(sys.implementation, "name", None)),
+            "pythonVersion": platform.python_version(),
+            "assemblies": loaded_assembly_versions(),
+        },
+        "document": {
+            "title": safe_text(document.Title),
+            "pathName": safe_text(document.PathName),
+            "isFamilyDocument": bool(document.IsFamilyDocument),
+            "cloud": get_cloud_identity(document),
+            "worksharing": get_worksharing_identity(document),
+        },
+        "modelIdentityCandidates": {
+            "projectInformationUniqueId": safe_text(project_information.UniqueId),
+            "projectInformationElementId": element_id_text(project_information.Id),
+            "checkedProjectParameters": checked_parameters,
+        },
+        "projectInformationParameters": sorted_parameters(project_information),
+        "warnings": warnings,
+    }
+
+
+try:
+    report = build_report()
+    output_path = resolve_output_path(get_input(0), "model-identity")
+    write_json(output_path, report)
+    OUT = {
+        "ok": True,
+        "filePath": output_path,
+        "projectInformationUniqueId": report["modelIdentityCandidates"][
+            "projectInformationUniqueId"
+        ],
+        "warnings": report["warnings"],
+        "report": report,
+    }
+except Exception as error:
+    OUT = {
+        "ok": False,
+        "error": safe_text(error),
+        "traceback": traceback.format_exc(),
+    }

dynamo/02_export_electrical_fixture_parameter_inventory.py

@@ -0,0 +1,517 @@
+"""Export all Electrical Fixtures instance/type parameters from Revit 2026.
+
+Optional Dynamo inputs:
+    IN[0]: output directory or complete .json file path
+    IN[1]: include empty parameters (default True)
+    IN[2]: maximum aggregated sample values (default 5)
+
+The script is read-only and performs no Revit transaction.
+"""
+
+import datetime
+import json
+import os
+import platform
+import sys
+import tempfile
+import traceback
+
+import clr
+
+clr.AddReference("RevitAPI")
+clr.AddReference("RevitServices")
+
+from Autodesk.Revit.DB import (  # noqa: E402
+    BuiltInCategory,
+    FilteredElementCollector,
+    ModelPathUtils,
+    StorageType,
+)
+from RevitServices.Persistence import DocumentManager  # noqa: E402
+
+
+def safe_text(value):
+    if value is None:
+        return None
+    try:
+        return str(value)
+    except Exception:
+        return None
+
+
+def element_id_text(element_id):
+    if element_id is None:
+        return None
+    try:
+        return str(element_id.Value)
+    except Exception:
+        try:
+            return str(element_id.IntegerValue)
+        except Exception:
+            return safe_text(element_id)
+
+
+def forge_type_id_text(value):
+    if value is None:
+        return None
+    try:
+        return value.TypeId
+    except Exception:
+        return safe_text(value)
+
+
+def parameter_value(parameter):
+    result = {"hasValue": False, "raw": None, "display": None}
+    try:
+        result["hasValue"] = bool(parameter.HasValue)
+    except Exception:
+        pass
+
+    try:
+        storage_type = parameter.StorageType
+        if storage_type == StorageType.String:
+            result["raw"] = parameter.AsString()
+        elif storage_type == StorageType.Integer:
+            result["raw"] = int(parameter.AsInteger())
+        elif storage_type == StorageType.Double:
+            result["raw"] = float(parameter.AsDouble())
+        elif storage_type == StorageType.ElementId:
+            result["raw"] = element_id_text(parameter.AsElementId())
+    except Exception as error:
+        result["readError"] = safe_text(error)
+
+    try:
+        result["display"] = parameter.AsValueString()
+    except Exception:
+        pass
+    return result
+
+
+def describe_parameter(parameter, scope):
+    definition = None
+    try:
+        definition = parameter.Definition
+    except Exception:
+        pass
+
+    name = None
+    data_type = None
+    group_type = None
+    if definition is not None:
+        try:
+            name = definition.Name
+        except Exception:
+            pass
+        try:
+            data_type = forge_type_id_text(definition.GetDataType())
+        except Exception:
+            pass
+        try:
+            group_type = forge_type_id_text(definition.GetGroupTypeId())
+        except Exception:
+            pass
+
+    is_shared = False
+    try:
+        is_shared = bool(parameter.IsShared)
+    except Exception:
+        pass
+
+    shared_guid = None
+    if is_shared:
+        try:
+            shared_guid = str(parameter.GUID)
+        except Exception:
+            pass
+
+    unit_type = None
+    try:
+        unit_type = forge_type_id_text(parameter.GetUnitTypeId())
+    except Exception:
+        pass
+
+    try:
+        storage_type = str(parameter.StorageType)
+    except Exception:
+        storage_type = None
+
+    try:
+        is_read_only = bool(parameter.IsReadOnly)
+    except Exception:
+        is_read_only = None
+
+    try:
+        user_modifiable = bool(parameter.UserModifiable)
+    except Exception:
+        user_modifiable = None
+
+    return {
+        "scope": scope,
+        "name": name,
+        "parameterId": element_id_text(getattr(parameter, "Id", None)),
+        "isShared": is_shared,
+        "sharedGuid": shared_guid,
+        "storageType": storage_type,
+        "dataTypeId": data_type,
+        "groupTypeId": group_type,
+        "unitTypeId": unit_type,
+        "isReadOnly": is_read_only,
+        "userModifiable": user_modifiable,
+        "value": parameter_value(parameter),
+    }
+
+
+def has_meaningful_value(parameter_description):
+    value = parameter_description.get("value", {})
+    return bool(value.get("hasValue")) or value.get("raw") not in (None, "") or value.get(
+        "display"
+    ) not in (None, "")
+
+
+def read_parameters(element, scope, include_empty):
+    result = []
+    try:
+        for parameter in element.Parameters:
+            description = describe_parameter(parameter, scope)
+            if include_empty or has_meaningful_value(description):
+                result.append(description)
+    except Exception as error:
+        return [], [safe_text(error)]
+    result.sort(
+        key=lambda parameter: (
+            (parameter.get("name") or "").casefold(),
+            parameter.get("parameterId") or "",
+        )
+    )
+    return result, []
+
+
+def read_space(element, document):
+    try:
+        space = element.Space
+    except Exception as error:
+        return None, safe_text(error)
+    if space is None:
+        return None, None
+
+    level_name = None
+    try:
+        level = document.GetElement(space.LevelId)
+        level_name = None if level is None else safe_text(level.Name)
+    except Exception:
+        pass
+
+    return {
+        "uniqueId": safe_text(space.UniqueId),
+        "elementId": element_id_text(space.Id),
+        "number": safe_text(getattr(space, "Number", None)),
+        "name": safe_text(getattr(space, "Name", None)),
+        "levelName": level_name,
+    }, None
+
+
+def read_family_identity(element, document):
+    symbol = None
+    try:
+        symbol = element.Symbol
+    except Exception:
+        try:
+            symbol = document.GetElement(element.GetTypeId())
+        except Exception:
+            pass
+
+    family_name = None
+    type_name = None
+    type_unique_id = None
+    type_element_id = None
+    if symbol is not None:
+        try:
+            family_name = safe_text(symbol.Family.Name)
+        except Exception:
+            family_name = safe_text(getattr(symbol, "FamilyName", None))
+        type_name = safe_text(getattr(symbol, "Name", None))
+        type_unique_id = safe_text(getattr(symbol, "UniqueId", None))
+        type_element_id = element_id_text(getattr(symbol, "Id", None))
+
+    return {
+        "familyName": family_name,
+        "typeName": type_name,
+        "typeUniqueId": type_unique_id,
+        "typeElementId": type_element_id,
+    }, symbol
+
+
+def parameter_inventory_key(parameter):
+    stable_id = parameter.get("sharedGuid") or parameter.get("parameterId") or ""
+    return "|".join(
+        (
+            parameter.get("scope") or "",
+            stable_id,
+            parameter.get("name") or "",
+            parameter.get("dataTypeId") or "",
+        )
+    )
+
+
+def sample_value_key(value):
+    return json.dumps(value, ensure_ascii=False, sort_keys=True, separators=(",", ":"))
+
+
+def add_to_inventory(inventory, parameter, max_samples):
+    key = parameter_inventory_key(parameter)
+    entry = inventory.get(key)
+    if entry is None:
+        entry = {
+            "scope": parameter.get("scope"),
+            "name": parameter.get("name"),
+            "parameterId": parameter.get("parameterId"),
+            "isShared": parameter.get("isShared"),
+            "sharedGuid": parameter.get("sharedGuid"),
+            "storageType": parameter.get("storageType"),
+            "dataTypeId": parameter.get("dataTypeId"),
+            "groupTypeId": parameter.get("groupTypeId"),
+            "unitTypeId": parameter.get("unitTypeId"),
+            "occurrenceCount": 0,
+            "populatedCount": 0,
+            "sampleValues": [],
+            "_sampleKeys": set(),
+        }
+        inventory[key] = entry
+    entry["occurrenceCount"] += 1
+    if has_meaningful_value(parameter):
+        entry["populatedCount"] += 1
+    value = parameter.get("value")
+    value_key = sample_value_key(value)
+    if len(entry["sampleValues"]) < max_samples and value_key not in entry["_sampleKeys"]:
+        entry["_sampleKeys"].add(value_key)
+        entry["sampleValues"].append(value)
+
+
+def finalize_inventory(inventory):
+    result = []
+    for entry in inventory.values():
+        clean_entry = dict(entry)
+        clean_entry.pop("_sampleKeys", None)
+        result.append(clean_entry)
+    return sorted(
+        result,
+        key=lambda entry: (
+            entry.get("scope") or "",
+            (entry.get("name") or "").casefold(),
+            entry.get("sharedGuid") or entry.get("parameterId") or "",
+        ),
+    )
+
+
+def loaded_assembly_versions():
+    result = {}
+    try:
+        from System import AppDomain
+
+        for assembly in AppDomain.CurrentDomain.GetAssemblies():
+            try:
+                name = assembly.GetName()
+                simple_name = str(name.Name)
+                if simple_name in (
+                    "DynamoCore",
+                    "DynamoCoreWpf",
+                    "DynamoRevitDS",
+                    "RevitAPI",
+                    "RevitServices",
+                ):
+                    result[simple_name] = str(name.Version)
+            except Exception:
+                continue
+    except Exception:
+        pass
+    return dict(sorted(result.items()))
+
+
+def resolve_output_path(configured_path):
+    timestamp = datetime.datetime.now().strftime("%Y%m%d-%H%M%S")
+    default_directory = os.path.join(tempfile.gettempdir(), "leistungsbilanz-dynamo")
+    raw_path = safe_text(configured_path)
+    if raw_path is None or not raw_path.strip():
+        directory = default_directory
+        file_path = os.path.join(
+            directory, "electrical-fixture-parameters-" + timestamp + ".json"
+        )
+    else:
+        expanded = os.path.abspath(os.path.expandvars(os.path.expanduser(raw_path.strip())))
+        if expanded.lower().endswith(".json"):
+            file_path = expanded
+            directory = os.path.dirname(file_path)
+        else:
+            directory = expanded
+            file_path = os.path.join(
+                directory, "electrical-fixture-parameters-" + timestamp + ".json"
+            )
+    if not directory:
+        directory = os.getcwd()
+    if not os.path.isdir(directory):
+        os.makedirs(directory)
+    return file_path
+
+
+def write_json(file_path, payload):
+    temporary_path = file_path + ".tmp"
+    with open(temporary_path, "w", encoding="utf-8", newline="\n") as output:
+        json.dump(payload, output, ensure_ascii=False, indent=2, sort_keys=True)
+        output.write("\n")
+    os.replace(temporary_path, file_path)
+
+
+def get_input(index, default=None):
+    values = globals().get("IN", [])
+    try:
+        value = values[index]
+        return default if value is None else value
+    except Exception:
+        return default
+
+
+def build_report(include_empty, max_samples):
+    document = DocumentManager.Instance.CurrentDBDocument
+    if document is None:
+        raise RuntimeError("No active Revit document is available.")
+    if document.IsFamilyDocument:
+        raise RuntimeError("Open a Revit project document, not a family document.")
+
+    application = document.Application
+    collector = (
+        FilteredElementCollector(document)
+        .OfCategory(BuiltInCategory.OST_ElectricalFixtures)
+        .WhereElementIsNotElementType()
+    )
+    source_elements = list(collector)
+    source_elements.sort(key=lambda element: safe_text(element.UniqueId) or "")
+
+    elements = []
+    types_by_unique_id = {}
+    inventory = {}
+    errors = []
+    elements_without_space = 0
+
+    for element in source_elements:
+        element_errors = []
+        try:
+            family_identity, symbol = read_family_identity(element, document)
+            instance_parameters, parameter_errors = read_parameters(
+                element, "instance", include_empty
+            )
+            element_errors.extend(parameter_errors)
+            for parameter in instance_parameters:
+                add_to_inventory(inventory, parameter, max_samples)
+
+            type_unique_id = family_identity.get("typeUniqueId")
+            if symbol is not None and type_unique_id and type_unique_id not in types_by_unique_id:
+                type_parameters, type_errors = read_parameters(symbol, "type", include_empty)
+                element_errors.extend(type_errors)
+                for parameter in type_parameters:
+                    add_to_inventory(inventory, parameter, max_samples)
+                types_by_unique_id[type_unique_id] = {
+                    **family_identity,
+                    "parameters": type_parameters,
+                }
+
+            space, space_error = read_space(element, document)
+            if space_error:
+                element_errors.append("MEP Space: " + space_error)
+            if space is None:
+                elements_without_space += 1
+
+            elements.append(
+                {
+                    "uniqueId": safe_text(element.UniqueId),
+                    "elementId": element_id_text(element.Id),
+                    "categoryName": safe_text(
+                        None if element.Category is None else element.Category.Name
+                    ),
+                    "family": family_identity,
+                    "space": space,
+                    "instanceParameters": instance_parameters,
+                    "warnings": element_errors,
+                }
+            )
+        except Exception as error:
+            errors.append(
+                {
+                    "uniqueId": safe_text(getattr(element, "UniqueId", None)),
+                    "elementId": element_id_text(getattr(element, "Id", None)),
+                    "error": safe_text(error),
+                }
+            )
+
+    return {
+        "reportSchemaVersion": 1,
+        "generatedAt": datetime.datetime.now(datetime.timezone.utc).isoformat(),
+        "readOnly": True,
+        "complete": len(errors) == 0,
+        "scope": {
+            "builtInCategory": "OST_ElectricalFixtures",
+            "wholeDocument": True,
+            "elementTypesExcluded": True,
+            "includeEmptyParameters": include_empty,
+        },
+        "environment": {
+            "revitVersionNumber": safe_text(getattr(application, "VersionNumber", None)),
+            "revitVersionName": safe_text(getattr(application, "VersionName", None)),
+            "revitSubVersionNumber": safe_text(
+                getattr(application, "SubVersionNumber", None)
+            ),
+            "pythonImplementation": safe_text(getattr(sys.implementation, "name", None)),
+            "pythonVersion": platform.python_version(),
+            "assemblies": loaded_assembly_versions(),
+        },
+        "document": {
+            "title": safe_text(document.Title),
+            "pathName": safe_text(document.PathName),
+            "projectInformationUniqueId": safe_text(document.ProjectInformation.UniqueId),
+        },
+        "summary": {
+            "elementCount": len(source_elements),
+            "exportedElementCount": len(elements),
+            "typeCount": len(types_by_unique_id),
+            "parameterDefinitionCount": len(inventory),
+            "elementsWithoutMepSpace": elements_without_space,
+            "elementErrorCount": len(errors),
+        },
+        "parameterInventory": finalize_inventory(inventory),
+        "types": sorted(
+            types_by_unique_id.values(),
+            key=lambda entry: (
+                (entry.get("familyName") or "").casefold(),
+                (entry.get("typeName") or "").casefold(),
+                entry.get("typeUniqueId") or "",
+            ),
+        ),
+        "elements": elements,
+        "errors": errors,
+    }
+
+
+try:
+    include_empty_input = get_input(1, True)
+    include_empty = bool(include_empty_input)
+    try:
+        max_samples = int(get_input(2, 5))
+    except Exception:
+        max_samples = 5
+    max_samples = max(0, min(max_samples, 50))
+
+    report = build_report(include_empty, max_samples)
+    output_path = resolve_output_path(get_input(0))
+    write_json(output_path, report)
+    OUT = {
+        "ok": True,
+        "filePath": output_path,
+        "complete": report["complete"],
+        "summary": report["summary"],
+        "errors": report["errors"],
+    }
+except Exception as error:
+    OUT = {
+        "ok": False,
+        "error": safe_text(error),
+        "traceback": traceback.format_exc(),
+    }

dynamo/README.md

@@ -0,0 +1,69 @@
+# Revit 2026 / Dynamo diagnostics
+
+This directory contains self-contained Python scripts for a Dynamo **Python
+Script** node. They use only Dynamo's built-in Revit integration, the Revit API
+and the Python standard library. No Dynamo package is required.
+
+The scripts are read-only. They do not start a Revit transaction and do not
+change the open model.
+
+## Python engine
+
+Use the built-in `CPython3` engine in Revit 2026. Autodesk ships Dynamo with
+Revit; optional PythonNet3 packages are not required by these diagnostics.
+
+## 01 - Check model identity
+
+File: `01_check_model_identity.py`
+
+The script reports:
+
+- Revit, Dynamo and Python versions;
+- `ProjectInformation.UniqueId` as a native model-identity candidate;
+- all occurrences and values of `LB_ModelId` and `LB_ProjectId` on Project
+  Information;
+- all Project Information parameters;
+- optional cloud/worksharing identity information when the API exposes it.
+
+Input `IN[0]` is optional. It may be either an output directory or a complete
+`.json` file path. With no input, the report is written below the current
+Windows temporary directory in `leistungsbilanz-dynamo`.
+
+## 02 - Inventory Electrical Fixtures parameters
+
+File: `02_export_electrical_fixture_parameter_inventory.py`
+
+The script reads every instance of
+`BuiltInCategory.OST_ElectricalFixtures` in the complete current document. It
+exports:
+
+- element, family, type and MEP Space identities;
+- every instance parameter and value;
+- every unique family-type parameter and value;
+- an aggregated parameter inventory with occurrence counts and sample values;
+- per-element warnings instead of aborting at the first unreadable element.
+
+Inputs:
+
+- `IN[0]` (optional): output directory or complete `.json` path;
+- `IN[1]` (optional): include empty parameters, default `true`;
+- `IN[2]` (optional): maximum sample values per aggregated parameter, default
+  `5`.
+
+The default output location is again the Windows temporary directory. The
+generated report can contain model paths and project-specific parameter values;
+review it before sharing or committing it.
+
+## Running a script
+
+1. Open the target model in Revit 2026.
+2. Open Dynamo from **Manage > Visual Programming > Dynamo**.
+3. Create a graph and add a **Python Script** node.
+4. Select the `CPython3` engine for the node.
+5. Copy the complete content of the desired `.py` file into the node.
+6. Optionally connect a String node containing the output path to `IN[0]`.
+7. Run the graph and inspect `OUT` for status, counts and the generated path.
+
+For the first test, run `01_check_model_identity.py` in the Revit main model.
+Then run the parameter inventory. Keep both generated JSON files so their
+structure can be checked before the production snapshot DTO is finalized.

next.config.mjs

@@ -2,6 +2,12 @@
 const apiInternalUrl = (process.env.API_INTERNAL_URL || "http://localhost:3000").replace(/\/$/, "");
 
 const nextConfig = {
+  allowedDevOrigins: [
+    "192.168.3.13",
+    "docker01.int.jappel.io",
+    "lb.jappel.io"
+  ],
+
   typescript: {
     tsconfigPath: "./tsconfig.next.json",
   },
@@ -20,3 +26,4 @@ const nextConfig = {
 };
 
 export default nextConfig;
+

package-lock.json

@@ -22,12 +22,15 @@
       "devDependencies": {
         "@types/better-sqlite3": "^7.6.13",
         "@types/express": "^5.0.6",
-        "@types/node": "^25.6.0",
+        "@types/node": "^24.10.1",
         "@types/react": "^19.2.14",
         "@types/react-dom": "^19.2.3",
         "drizzle-kit": "^0.31.10",
         "tsx": "^4.21.0",
         "typescript": "^6.0.3"
+      },
+      "engines": {
+        "node": "24.x"
       }
     },
     "node_modules/@drizzle-team/brocli": {
@@ -1514,12 +1517,13 @@
       "dev": true
     },
     "node_modules/@types/node": {
-      "version": "25.6.0",
-      "resolved": "https://registry.npmjs.org/@types/node/-/node-25.6.0.tgz",
-      "integrity": "sha512-+qIYRKdNYJwY3vRCZMdJbPLJAtGjQBudzZzdzwQYkEPQd+PJGixUL5QfvCLDaULoLv+RhT3LDkwEfKaAkgSmNQ==",
+      "version": "24.13.3",
+      "resolved": "https://registry.npmjs.org/@types/node/-/node-24.13.3.tgz",
+      "integrity": "sha512-Dh8vAsV36ig5wa9OX4pXvMc9D3Veibfw2wix0CUwYODLD8nkj9UsLjASr49nPg+2eKzxhBV+v7L8pXvT4e639Q==",
       "devOptional": true,
+      "license": "MIT",
       "dependencies": {
-        "undici-types": "~7.19.0"
+        "undici-types": "~7.18.0"
       }
     },
     "node_modules/@types/qs": {
@@ -3688,10 +3692,11 @@
       }
     },
     "node_modules/undici-types": {
-      "version": "7.19.2",
-      "resolved": "https://registry.npmjs.org/undici-types/-/undici-types-7.19.2.tgz",
-      "integrity": "sha512-qYVnV5OEm2AW8cJMCpdV20CDyaN3g0AjDlOGf1OW4iaDEx8MwdtChUp4zu4H0VP3nDRF/8RKWH+IPp9uW0YGZg==",
-      "devOptional": true
+      "version": "7.18.2",
+      "resolved": "https://registry.npmjs.org/undici-types/-/undici-types-7.18.2.tgz",
+      "integrity": "sha512-AsuCzffGHJybSaRrmr5eHr81mwJU3kjw6M+uprWvCXiNeN9SOGwQ3Jn8jb8m3Z6izVgknn1R0FTCEAP2QrLY/w==",
+      "devOptional": true,
+      "license": "MIT"
     },
     "node_modules/unpipe": {
       "version": "1.0.0",

package.json

@@ -3,6 +3,9 @@
   "version": "1.0.0",
   "description": "Spreadsheet-style circuit list editor for electrical distribution planning",
   "main": "dist/server/index.js",
+  "engines": {
+    "node": "24.x"
+  },
   "scripts": {
     "dev": "npm run dev:api",
     "dev:api": "tsx watch src/server/index.ts",
@@ -10,6 +13,9 @@
     "docker:up": "docker compose up --build --detach",
     "docker:down": "docker compose down",
     "docker:logs": "docker compose logs --follow",
+    "docker:dev:up": "docker compose -f compose.dev.yaml up --build --detach",
+    "docker:dev:down": "docker compose -f compose.dev.yaml down",
+    "docker:dev:logs": "docker compose -f compose.dev.yaml logs --follow",
     "build": "npm run build:api",
     "build:api": "tsc -p tsconfig.json",
     "build:web": "next build",
@@ -40,7 +46,7 @@
   "devDependencies": {
     "@types/better-sqlite3": "^7.6.13",
     "@types/express": "^5.0.6",
-    "@types/node": "^25.6.0",
+    "@types/node": "^24.10.1",
     "@types/react": "^19.2.14",
     "@types/react-dom": "^19.2.3",
     "drizzle-kit": "^0.31.10",

src/app/globals.css

@@ -3,7 +3,13 @@
    Bootstrap bleibt Basis für Formulare/Tabellen/Modals; wir tönen die
    vorhandenen Bootstrap-Komponenten über deren eigene --bs-btn-*-Variablen
    um (globals.css lädt nach bootstrap.min.css, gleiche Spezifität gewinnt
-   per Ladereihenfolge) statt Bootstrap zu ersetzen. */
+   per Ladereihenfolge) statt Bootstrap zu ersetzen.
+
+   Dark mode: Bootstrap schaltet seine eigenen Komponenten (Formulare,
+   Modals, Cards, Alerts, ...) automatisch um, sobald `data-bs-theme="dark"`
+   auf <html> steht (gesetzt von ThemeToggle.tsx, persistiert in
+   localStorage). Der custom Stromkreis-Grid nutzt dafür dieselben
+   Tokens unten, per `:root[data-bs-theme="dark"]` überschrieben. */
 :root {
   --color-primary: #1c3f52; /* Petrol */
   --color-primary-dark: #0f2733; /* Petrol Dark */
@@ -33,6 +39,105 @@
   --space-xl: 40px;
 
   --radius: 12px;
+
+  /* ── Grid/Editor-Tokens (hell) ──────────────────────────────────────── */
+  --panel-bg: #ffffff;
+  --panel-bg-subtle: #f8fafc;
+  --panel-border: #d9dee8;
+  --panel-border-strong: #c4cddc;
+  --input-border: #9fb6e0;
+  --text-strong: #1f2937;
+  --text-muted: #4b5563;
+  --text-faint: #6b7280;
+  --text-subtle: #475569;
+
+  --accent-blue: #2563eb;
+  --accent-blue-soft-bg: #eff6ff;
+  --accent-blue-border: #bfdbfe;
+  --accent-blue-strong-border: #4c7dd9;
+  --accent-blue-drop-border: #2b6cb0;
+  --accent-blue-marker: #1d4ed8;
+
+  --surface-selected: #eaf1ff;
+  --surface-header-row: #e8eef8;
+  --surface-component-header: #e2e8f0;
+  --surface-component-group: #f8fafc;
+  --surface-component-footer: #f1f5f9;
+  --surface-hover: #f3f4f6;
+
+  --grid-warn: #d97706;
+  --grid-warn-bg: #fff7ed;
+  --grid-warn-strong: #9a3412;
+  --grid-danger: #c2410c;
+
+  --notice-info-bg: #ebf3ff;
+  --notice-info-border: #bad1f7;
+  --notice-error-bg: #fdecec;
+  --notice-error-border: #f5b5b5;
+  --notice-warning-bg: #fff7ed;
+  --notice-warning-border: #fdba74;
+  --notice-muted-bg: #f6f6f6;
+  --notice-muted-border: #e4e4e4;
+
+  --shadow-soft: rgba(15, 39, 51, 0.07);
+  --shadow-strong: rgba(15, 39, 51, 0.28);
+  --shadow-menu: rgba(0, 0, 0, 0.12);
+  --shadow-drawer: rgba(31, 41, 55, 0.22);
+}
+
+:root[data-bs-theme="dark"] {
+  --color-ink: #e6ecef;
+  --color-ink-soft: #9db0b8;
+  --color-bg: #141b20;
+  --color-surface: #0f1519;
+  --color-border: #2a3941;
+  --color-danger: #e2664f;
+  --color-danger-bg: #33201c;
+  --color-warn: #e0983f;
+
+  /* ── Grid/Editor-Tokens (dunkel) ────────────────────────────────────── */
+  --panel-bg: #182229;
+  --panel-bg-subtle: #1c2830;
+  --panel-border: #2c3c45;
+  --panel-border-strong: #374a54;
+  --input-border: #3c5568;
+  --text-strong: #e6ecef;
+  --text-muted: #aebdc4;
+  --text-faint: #8798a0;
+  --text-subtle: #9db0b8;
+
+  --accent-blue: #6fa2f7;
+  --accent-blue-soft-bg: #17253a;
+  --accent-blue-border: #2c4a72;
+  --accent-blue-strong-border: #6fa2f7;
+  --accent-blue-drop-border: #4f84d6;
+  --accent-blue-marker: #6fa2f7;
+
+  --surface-selected: #17253a;
+  --surface-header-row: #1a262f;
+  --surface-component-header: #202e37;
+  --surface-component-group: #1a262f;
+  --surface-component-footer: #182229;
+  --surface-hover: #1f2b33;
+
+  --grid-warn: #e0983f;
+  --grid-warn-bg: #2e2214;
+  --grid-warn-strong: #f0b880;
+  --grid-danger: #e2825f;
+
+  --notice-info-bg: #182839;
+  --notice-info-border: #2c4a72;
+  --notice-error-bg: #33201c;
+  --notice-error-border: #5c332c;
+  --notice-warning-bg: #2e2214;
+  --notice-warning-border: #6b4a1c;
+  --notice-muted-bg: #1b2226;
+  --notice-muted-border: #2a3338;
+
+  --shadow-soft: rgba(0, 0, 0, 0.35);
+  --shadow-strong: rgba(0, 0, 0, 0.55);
+  --shadow-menu: rgba(0, 0, 0, 0.45);
+  --shadow-drawer: rgba(0, 0, 0, 0.55);
 }
 
 html {
@@ -109,6 +214,12 @@ a {
   --bs-alert-border-color: #b6e2ce;
 }
 
+:root[data-bs-theme="dark"] .alert-success {
+  --bs-alert-color: #7fd6a7;
+  --bs-alert-bg: #16291f;
+  --bs-alert-border-color: #205a38;
+}
+
 /* ── App-Shell / Seitenleiste (nur auf der Projektseite) ────────────────── */
 
 .app-shell {
@@ -165,6 +276,7 @@ a {
   flex-direction: column;
   gap: 2px;
   padding: 12px;
+  flex: 1;
 }
 
 .sidebar-section-label {
@@ -210,6 +322,32 @@ a {
   justify-content: center;
 }
 
+.sidebar-footer {
+  padding: 12px;
+  border-top: 1px solid rgba(255, 255, 255, 0.12);
+}
+
+.sidebar-theme-toggle {
+  display: flex;
+  align-items: center;
+  gap: 10px;
+  padding: 10px 14px;
+  border-radius: 8px;
+  color: #c7d6e0;
+  font-size: 0.92rem;
+  font-weight: 500;
+  border: 1px solid rgba(255, 255, 255, 0.16);
+  background: rgba(255, 255, 255, 0.06);
+  width: 100%;
+  text-align: left;
+  cursor: pointer;
+}
+
+.sidebar-theme-toggle:hover {
+  background: rgba(255, 255, 255, 0.14);
+  color: #fff;
+}
+
 .app-shell-content {
   width: 100%;
   min-width: 0;
@@ -230,6 +368,10 @@ a {
   color: var(--color-primary);
 }
 
+:root[data-bs-theme="dark"] .page-header h1 {
+  color: var(--color-accent-pale);
+}
+
 .kicker {
   font-size: 0.72rem;
   letter-spacing: 0.12em;
@@ -262,7 +404,7 @@ a {
 a.kpi:hover {
   color: inherit;
   text-decoration: none;
-  box-shadow: 0 3px 8px rgba(15, 39, 51, 0.07), 0 16px 32px -14px rgba(15, 39, 51, 0.28);
+  box-shadow: 0 3px 8px var(--shadow-soft), 0 16px 32px -14px var(--shadow-strong);
   transform: translateY(-1px);
 }
 
@@ -285,12 +427,16 @@ a.kpi:hover {
   color: var(--color-primary);
 }
 
+:root[data-bs-theme="dark"] .kpi-value {
+  color: var(--color-accent-pale);
+}
+
 .card {
   border-radius: var(--radius);
   border-top: 3px solid var(--color-primary);
   box-shadow:
-    0 1px 2px rgba(15, 39, 51, 0.05),
-    0 10px 24px -14px rgba(15, 39, 51, 0.22);
+    0 1px 2px var(--shadow-soft),
+    0 10px 24px -14px var(--shadow-strong);
 }
 
 .card-header {
@@ -300,6 +446,10 @@ a.kpi:hover {
   border-bottom: 1px solid var(--color-border);
 }
 
+:root[data-bs-theme="dark"] .card-header {
+  color: var(--color-accent-pale);
+}
+
 .table td input.form-control-sm,
 .table td select.form-select-sm {
   min-width: 8rem;
@@ -320,13 +470,14 @@ a.kpi:hover {
   top: 0;
   z-index: 12;
   padding: 0.35rem 0;
-  background: #fff;
-  box-shadow: 0 1px 0 rgba(196, 205, 220, 0.8);
+  background: var(--panel-bg);
+  box-shadow: 0 1px 0 var(--panel-border-strong);
 }
 
 .editor-toolbar button {
-  border: 1px solid #c4cddc;
-  background: #fff;
+  border: 1px solid var(--panel-border-strong);
+  background: var(--panel-bg);
+  color: var(--text-strong);
   padding: 0.28rem 0.6rem;
   border-radius: 4px;
   font-size: 0.82rem;
@@ -337,8 +488,8 @@ a.kpi:hover {
 }
 
 .editor-toolbar .project-device-drawer-toggle {
-  border-color: #2563eb;
-  background: #2563eb;
+  border-color: var(--accent-blue);
+  background: var(--accent-blue);
   color: #fff;
   font-weight: 600;
 }
@@ -349,10 +500,10 @@ a.kpi:hover {
   align-items: center;
   gap: 0.35rem;
   padding: 0.4rem 0.5rem;
-  border: 1px solid #bfdbfe;
+  border: 1px solid var(--accent-blue-border);
   border-radius: 5px;
-  background: #eff6ff;
-  color: #1e3a5f;
+  background: var(--accent-blue-soft-bg);
+  color: var(--text-subtle);
   font-size: 0.78rem;
 }
 
@@ -362,10 +513,10 @@ a.kpi:hover {
 
 .active-view-chip,
 .active-view-reset {
-  border: 1px solid #93b4df;
+  border: 1px solid var(--accent-blue-border);
   border-radius: 999px;
-  background: #fff;
-  color: #1e3a5f;
+  background: var(--panel-bg);
+  color: var(--text-subtle);
   padding: 0.18rem 0.48rem;
   font-size: 0.76rem;
   cursor: pointer;
@@ -373,7 +524,7 @@ a.kpi:hover {
 
 .active-view-chip:hover,
 .active-view-reset:hover {
-  border-color: #2563eb;
+  border-color: var(--accent-blue);
 }
 
 .active-view-reset {
@@ -386,9 +537,9 @@ a.kpi:hover {
   grid-template-columns: repeat(3, minmax(12rem, 1fr));
   gap: 0.5rem;
   padding: 0.55rem;
-  border: 1px solid #cbd5e1;
+  border: 1px solid var(--panel-border);
   border-radius: 5px;
-  background: #f8fafc;
+  background: var(--panel-bg-subtle);
 }
 
 .distribution-power-summary > div {
@@ -398,13 +549,13 @@ a.kpi:hover {
 }
 
 .distribution-power-summary span {
-  color: #475569;
+  color: var(--text-subtle);
   font-size: 0.74rem;
   line-height: 1.2;
 }
 
 .distribution-power-summary strong {
-  color: #172033;
+  color: var(--text-strong);
   font-size: 0.95rem;
 }
 
@@ -418,13 +569,13 @@ a.kpi:hover {
   position: absolute;
   z-index: 9;
   margin-top: 2rem;
-  border: 1px solid #cfd7e5;
-  background: #fff;
+  border: 1px solid var(--panel-border);
+  background: var(--panel-bg);
   border-radius: 5px;
-  box-shadow: 0 6px 16px rgba(0, 0, 0, 0.12);
+  box-shadow: 0 6px 16px var(--shadow-menu);
   padding: 0.55rem;
   width: 340px;
-  color: #1f2937;
+  color: var(--text-strong);
   text-align: left;
 }
 
@@ -444,7 +595,7 @@ a.kpi:hover {
 .column-settings-close {
   border: 0 !important;
   background: transparent !important;
-  color: #4b5563;
+  color: var(--text-muted);
   padding: 0.05rem 0.2rem !important;
   font-size: 1rem !important;
   line-height: 1;
@@ -453,7 +604,7 @@ a.kpi:hover {
 
 .column-settings-explanation {
   margin-bottom: 0.4rem;
-  color: #4b5563;
+  color: var(--text-muted);
   font-size: 0.72rem;
   line-height: 1.3;
 }
@@ -461,9 +612,11 @@ a.kpi:hover {
 .column-settings-search {
   width: 100%;
   margin-bottom: 0.4rem;
-  border: 1px solid #c4cddc;
+  border: 1px solid var(--panel-border-strong);
   border-radius: 4px;
   padding: 0.3rem 0.4rem;
+  background: var(--panel-bg);
+  color: var(--text-strong);
   font-size: 0.76rem;
 }
 
@@ -473,7 +626,7 @@ a.kpi:hover {
   gap: 0.15rem;
   max-height: 300px;
   overflow: auto;
-  border: 1px solid #e1e6ef;
+  border: 1px solid var(--panel-border);
   border-radius: 4px;
   padding: 0.25rem;
 }
@@ -489,8 +642,8 @@ a.kpi:hover {
 }
 
 .column-settings-item.selected {
-  border-color: #bfdbfe;
-  background: #eff6ff;
+  border-color: var(--accent-blue-border);
+  background: var(--accent-blue-soft-bg);
 }
 
 .column-settings-item.dragging {
@@ -498,12 +651,12 @@ a.kpi:hover {
 }
 
 .column-settings-item.drop-target {
-  border-color: #2b6cb0;
-  background: #ebf4ff;
+  border-color: var(--accent-blue-drop-border);
+  background: var(--accent-blue-soft-bg);
 }
 
 .column-settings-item.locked {
-  background: #f7fafc;
+  background: var(--panel-bg-subtle);
 }
 
 .column-visibility-button {
@@ -530,7 +683,7 @@ a.kpi:hover {
   flex: 0 0 1rem;
   align-items: center;
   justify-content: center;
-  color: #1d4ed8;
+  color: var(--accent-blue-marker);
   font-weight: 700;
 }
 
@@ -540,8 +693,9 @@ a.kpi:hover {
 }
 
 .column-settings-order button {
-  border: 1px solid #c4cddc;
-  background: #fff;
+  border: 1px solid var(--panel-border-strong);
+  background: var(--panel-bg);
+  color: var(--text-strong);
   border-radius: 3px;
   font-size: 0.72rem;
   padding: 0.08rem 0.28rem;
@@ -549,8 +703,8 @@ a.kpi:hover {
 
 .tree-grid-wrap {
   overflow: auto;
-  border: 1px solid #d9dee8;
-  background: #fff;
+  border: 1px solid var(--panel-border);
+  background: var(--panel-bg);
   width: 100%;
   max-width: 100%;
   min-width: 0;
@@ -560,7 +714,7 @@ a.kpi:hover {
 
 .column-settings-empty {
   padding: 0.55rem 0.35rem;
-  color: #6b7280;
+  color: var(--text-faint);
   font-size: 0.76rem;
 }
 
@@ -570,8 +724,8 @@ a.kpi:hover {
 }
 
 .column-settings-footer button.primary {
-  border-color: #2563eb;
-  background: #2563eb;
+  border-color: var(--accent-blue);
+  background: var(--accent-blue);
   color: #fff;
 }
 
@@ -583,8 +737,8 @@ a.kpi:hover {
 }
 
 .project-device-sidebar {
-  border: 1px solid #d9dee8;
-  background: #fff;
+  border: 1px solid var(--panel-border);
+  background: var(--panel-bg);
   padding: 0.6rem;
   display: flex;
   flex-direction: column;
@@ -594,14 +748,17 @@ a.kpi:hover {
 .project-device-sidebar h3 {
   margin: 0;
   font-size: 1rem;
+  color: var(--text-strong);
 }
 
 .project-device-sidebar input,
 .project-device-sidebar select {
   width: 100%;
-  border: 1px solid #cfd7e5;
+  border: 1px solid var(--panel-border-strong);
   border-radius: 4px;
   padding: 0.25rem 0.35rem;
+  background: var(--panel-bg);
+  color: var(--text-strong);
 }
 
 .project-device-list {
@@ -613,8 +770,9 @@ a.kpi:hover {
 }
 
 .project-device-item {
-  border: 1px solid #d5ddec;
-  background: #f8faff;
+  border: 1px solid var(--panel-border-strong);
+  background: var(--panel-bg-subtle);
+  color: var(--text-strong);
   text-align: left;
   padding: 0.4rem;
   border-radius: 4px;
@@ -625,8 +783,8 @@ a.kpi:hover {
 }
 
 .project-device-item.selected {
-  border-color: #4c7dd9;
-  background: #edf3ff;
+  border-color: var(--accent-blue-strong-border);
+  background: var(--accent-blue-soft-bg);
 }
 
 .project-device-item.dragging {
@@ -645,11 +803,13 @@ a.kpi:hover {
   flex-direction: column;
   gap: 0.2rem;
   font-size: 0.82rem;
+  color: var(--text-strong);
 }
 
 .sidebar-actions button {
-  border: 1px solid #c4cddc;
-  background: #fff;
+  border: 1px solid var(--panel-border-strong);
+  background: var(--panel-bg);
+  color: var(--text-strong);
   border-radius: 4px;
   padding: 0.3rem 0.45rem;
   font-size: 0.82rem;
@@ -660,18 +820,19 @@ a.kpi:hover {
   min-width: 0;
   border-collapse: collapse;
   font-size: 0.9rem;
+  color: var(--text-strong);
 }
 
 .tree-grid th,
 .tree-grid td {
-  border: 1px solid #e4e9f2;
+  border: 1px solid var(--panel-border);
   padding: 0.35rem 0.4rem;
   vertical-align: middle;
 }
 
 .tree-grid th {
   width: 1px;
-  background: #f4f7fb;
+  background: var(--panel-bg-subtle);
   position: sticky;
   top: 0;
   z-index: 2;
@@ -694,8 +855,9 @@ a.kpi:hover {
 .tree-grid .header-filter-btn {
   display: block;
   width: 100%;
-  border: 1px solid #c4cddc;
-  background: #fff;
+  border: 1px solid var(--panel-border-strong);
+  background: var(--panel-bg);
+  color: var(--text-strong);
   border-radius: 3px;
   font-size: 0.75rem;
   padding: 0.15rem 0.35rem;
@@ -712,7 +874,7 @@ a.kpi:hover {
   border: 0;
   background: transparent;
   padding: 0;
-  color: #1f2937;
+  color: var(--text-strong);
   font: inherit;
   font-size: 0.78rem;
   font-weight: 600;
@@ -733,7 +895,7 @@ a.kpi:hover {
   max-height: calc(100vh - 7rem);
   overflow: auto;
   border-radius: 0.5rem;
-  box-shadow: 0 0.75rem 2rem rgba(31, 41, 55, 0.22);
+  box-shadow: 0 0.75rem 2rem var(--shadow-drawer);
 }
 
 .project-device-drawer-header {
@@ -744,13 +906,14 @@ a.kpi:hover {
 }
 
 .project-device-drawer-header span {
-  color: #6b7280;
+  color: var(--text-faint);
   font-size: 0.75rem;
 }
 
 .project-device-drawer-header button {
-  border: 1px solid #c4cddc;
-  background: #fff;
+  border: 1px solid var(--panel-border-strong);
+  background: var(--panel-bg);
+  color: var(--text-strong);
   border-radius: 4px;
   padding: 0.25rem 0.4rem;
   font-size: 0.78rem;
@@ -762,23 +925,24 @@ a.kpi:hover {
 }
 
 .tree-grid .sort-indicator {
-  color: #2563eb;
+  color: var(--accent-blue);
   font-size: 0.85rem;
 }
 
 .tree-grid .header-filter-btn.active {
-  border-color: #2563eb;
-  color: #2563eb;
-  background: #eff6ff;
+  border-color: var(--accent-blue);
+  color: var(--accent-blue);
+  background: var(--accent-blue-soft-bg);
 }
 
 .tree-grid .header-filter-menu {
   position: absolute;
   z-index: 7;
   margin-top: 0.2rem;
-  border: 1px solid #cfd7e5;
-  background: #fff;
-  box-shadow: 0 6px 16px rgba(0, 0, 0, 0.12);
+  border: 1px solid var(--panel-border);
+  background: var(--panel-bg);
+  color: var(--text-strong);
+  box-shadow: 0 6px 16px var(--shadow-menu);
   width: 300px;
   padding: 0.55rem;
   text-align: left;
@@ -802,7 +966,7 @@ a.kpi:hover {
 .tree-grid .header-filter-close {
   border: 0;
   background: transparent;
-  color: #4b5563;
+  color: var(--text-muted);
   padding: 0.05rem 0.2rem;
   font-size: 1rem;
   line-height: 1;
@@ -817,13 +981,14 @@ a.kpi:hover {
 
 .tree-grid .header-filter-selection-actions span {
   margin-left: auto;
-  color: #4b5563;
+  color: var(--text-muted);
 }
 
 .tree-grid .header-filter-selection-actions button,
 .tree-grid .header-filter-footer button {
-  border: 1px solid #c4cddc;
-  background: #fff;
+  border: 1px solid var(--panel-border-strong);
+  background: var(--panel-bg);
+  color: var(--text-strong);
   border-radius: 3px;
   padding: 0.18rem 0.35rem;
   font-size: 0.72rem;
@@ -832,7 +997,7 @@ a.kpi:hover {
 
 .tree-grid .header-filter-explanation {
   margin-bottom: 0.4rem;
-  color: #4b5563;
+  color: var(--text-muted);
   font-size: 0.72rem;
   line-height: 1.3;
   white-space: normal;
@@ -840,9 +1005,11 @@ a.kpi:hover {
 
 .tree-grid .header-filter-search {
   width: 100%;
-  border: 1px solid #c4cddc;
+  border: 1px solid var(--panel-border-strong);
   border-radius: 4px;
   padding: 0.3rem 0.4rem;
+  background: var(--panel-bg);
+  color: var(--text-strong);
   font-size: 0.76rem;
 }
 
@@ -852,7 +1019,7 @@ a.kpi:hover {
   gap: 0.15rem;
   max-height: 210px;
   overflow: auto;
-  border: 1px solid #e1e6ef;
+  border: 1px solid var(--panel-border);
   border-radius: 4px;
   padding: 0.25rem;
 }
@@ -866,7 +1033,7 @@ a.kpi:hover {
   border-radius: 3px;
   background: transparent;
   padding: 0.25rem 0.3rem;
-  color: #1f2937;
+  color: var(--text-strong);
   font-weight: 400;
   font-size: 0.75rem;
   text-align: left;
@@ -874,17 +1041,17 @@ a.kpi:hover {
 }
 
 .tree-grid .header-filter-item:hover {
-  background: #f3f4f6;
+  background: var(--surface-hover);
 }
 
 .tree-grid .header-filter-item.selected {
-  border-color: #bfdbfe;
-  background: #eff6ff;
+  border-color: var(--accent-blue-border);
+  background: var(--accent-blue-soft-bg);
 }
 
 .tree-grid .header-filter-empty {
   padding: 0.45rem 0.25rem;
-  color: #6b7280;
+  color: var(--text-faint);
   font-size: 0.74rem;
 }
 
@@ -897,8 +1064,8 @@ a.kpi:hover {
 }
 
 .tree-grid .header-filter-footer button.primary {
-  border-color: #2563eb;
-  background: #2563eb;
+  border-color: var(--accent-blue);
+  background: var(--accent-blue);
   color: #fff;
 }
 
@@ -908,7 +1075,7 @@ a.kpi:hover {
 }
 
 .tree-grid .header-filter-warning {
-  color: #9a3412;
+  color: var(--grid-warn-strong);
   font-size: 0.7rem;
   white-space: normal;
 }
@@ -918,25 +1085,25 @@ a.kpi:hover {
 }
 
 .tree-grid .section-row td {
-  background: #e8eef8;
+  background: var(--surface-header-row);
   font-weight: 600;
 }
 
 .tree-grid .structure-component-row td {
   padding: 0.38rem 0.6rem;
-  border-bottom-color: #d8dee9;
+  border-bottom-color: var(--panel-border);
 }
 
 .tree-grid .structure-component-row.headerComponent td {
-  background: #e2e8f0;
+  background: var(--surface-component-header);
 }
 
 .tree-grid .structure-component-row.groupComponent td {
-  background: #f8fafc;
+  background: var(--surface-component-group);
 }
 
 .tree-grid .structure-component-row.footerComponent td {
-  background: #f1f5f9;
+  background: var(--surface-component-footer);
 }
 
 .tree-grid .structure-component-content {
@@ -952,7 +1119,7 @@ a.kpi:hover {
 }
 
 .tree-grid .structure-component-protection {
-  color: #475569;
+  color: var(--text-subtle);
   font-size: 0.78rem;
 }
 
@@ -969,7 +1136,7 @@ a.kpi:hover {
 }
 
 .tree-grid .structure-component-fixed {
-  color: #64748b;
+  color: var(--text-faint);
   font-size: 0.75rem;
 }
 
@@ -990,32 +1157,33 @@ a.kpi:hover {
 }
 
 .tree-grid .section-actions button {
-  border: 1px solid #c4cddc;
-  background: #fff;
+  border: 1px solid var(--panel-border-strong);
+  background: var(--panel-bg);
+  color: var(--text-strong);
   padding: 0.2rem 0.45rem;
   border-radius: 3px;
   font-size: 0.78rem;
 }
 
 .tree-grid .summary-row td {
-  background: #f3f7fd;
+  background: var(--panel-bg-subtle);
 }
 
 .tree-grid .device-row td:first-child {
-  color: #6b7280;
+  color: var(--text-faint);
 }
 
 .tree-grid .empty-circuit-row td {
-  background: #f8fbff;
+  background: var(--panel-bg-subtle);
 }
 
 .tree-grid tr.row-selected td {
-  background: #eaf1ff;
+  background: var(--surface-selected);
 }
 
 .tree-grid .placeholder-row td {
-  background: #f7f7f7;
-  color: #6b7280;
+  background: var(--panel-bg-subtle);
+  color: var(--text-faint);
   font-style: italic;
 }
 
@@ -1032,8 +1200,12 @@ a.kpi:hover {
     box-shadow 0.12s ease;
 }
 
+:root[data-bs-theme="dark"] .tree-grid .cell-protection-trigger {
+  color: var(--color-accent-pale);
+}
+
 .tree-grid .cell-protection-trigger:hover {
-  background: #eaf6f0;
+  background: rgba(63, 166, 107, 0.15);
   box-shadow: inset 0 0 0 1px var(--color-signal);
 }
 
@@ -1054,7 +1226,7 @@ a.kpi:hover {
 }
 
 .tree-grid .cell-selected {
-  outline: 2px solid #4c7dd9;
+  outline: 2px solid var(--accent-blue-strong-border);
   outline-offset: -2px;
 }
 
@@ -1065,28 +1237,30 @@ a.kpi:hover {
 }
 
 .tree-grid .section-title span {
-  color: #475569;
+  color: var(--text-subtle);
   font-size: 0.78rem;
   font-weight: 500;
 }
 
 .tree-grid .cell-invalid {
-  outline: 2px solid #c2410c;
+  outline: 2px solid var(--grid-danger);
   outline-offset: -2px;
-  background: #fff7ed !important;
+  background: var(--grid-warn-bg) !important;
 }
 
 .tree-grid .cell-invalid input {
-  border-color: #c2410c;
+  border-color: var(--grid-danger);
 }
 
 .tree-grid input,
 .tree-grid select {
   width: 100%;
   min-width: 5rem;
-  border: 1px solid #9fb6e0;
+  border: 1px solid var(--input-border);
   border-radius: 2px;
   padding: 0.2rem 0.3rem;
+  background: var(--panel-bg);
+  color: var(--text-strong);
 }
 
 .tree-grid .action-cell {
@@ -1095,26 +1269,27 @@ a.kpi:hover {
 }
 
 .tree-grid .action-cell button {
-  border: 1px solid #c4cddc;
-  background: #fff;
+  border: 1px solid var(--panel-border-strong);
+  background: var(--panel-bg);
+  color: var(--text-strong);
   padding: 0.2rem 0.45rem;
   border-radius: 3px;
   font-size: 0.78rem;
 }
 
 .tree-grid .drop-target-active {
-  box-shadow: inset 0 0 0 2px #4c7dd9;
-  background: #eef4ff !important;
+  box-shadow: inset 0 0 0 2px var(--accent-blue-strong-border);
+  background: var(--accent-blue-soft-bg) !important;
 }
 
 .tree-grid .drop-target-invalid {
-  box-shadow: inset 0 0 0 2px #d97706;
-  background: #fff7ed !important;
+  box-shadow: inset 0 0 0 2px var(--grid-warn);
+  background: var(--grid-warn-bg) !important;
 }
 
 .tree-grid .drop-target-confirm {
-  box-shadow: inset 0 0 0 2px #d97706;
-  background: #fffbeb !important;
+  box-shadow: inset 0 0 0 2px var(--grid-warn);
+  background: var(--grid-warn-bg) !important;
 }
 
 .tree-grid tr.circuit-insert-before td,
@@ -1128,7 +1303,7 @@ a.kpi:hover {
   left: -1px;
   right: -1px;
   top: -2px;
-  border-top: 4px solid #2563eb;
+  border-top: 4px solid var(--accent-blue);
   pointer-events: none;
 }
 
@@ -1141,7 +1316,7 @@ a.kpi:hover {
   height: 0;
   border-top: 7px solid transparent;
   border-bottom: 7px solid transparent;
-  border-left: 10px solid #2563eb;
+  border-left: 10px solid var(--accent-blue);
   pointer-events: none;
 }
 
@@ -1151,7 +1326,7 @@ a.kpi:hover {
   left: -1px;
   right: -1px;
   bottom: -2px;
-  border-bottom: 4px solid #2563eb;
+  border-bottom: 4px solid var(--accent-blue);
   pointer-events: none;
 }
 
@@ -1164,13 +1339,13 @@ a.kpi:hover {
   height: 0;
   border-top: 7px solid transparent;
   border-bottom: 7px solid transparent;
-  border-left: 10px solid #2563eb;
+  border-left: 10px solid var(--accent-blue);
   pointer-events: none;
 }
 
 .drop-hint {
   font-size: 0.75rem;
-  color: #1f4ea3;
+  color: var(--accent-blue-marker);
   font-weight: 600;
 }
 
@@ -1178,21 +1353,22 @@ a.kpi:hover {
   padding: 0.5rem 0.75rem;
   border-radius: 4px;
   border: 1px solid transparent;
+  color: var(--text-strong);
 }
 
 .notice.info {
-  background: #ebf3ff;
-  border-color: #bad1f7;
+  background: var(--notice-info-bg);
+  border-color: var(--notice-info-border);
 }
 
 .notice.error {
-  background: #fdecec;
-  border-color: #f5b5b5;
+  background: var(--notice-error-bg);
+  border-color: var(--notice-error-border);
 }
 
 .notice.warning {
-  background: #fff7ed;
-  border-color: #fdba74;
+  background: var(--notice-warning-bg);
+  border-color: var(--notice-warning-border);
 }
 
 .editor-error-notice {
@@ -1203,12 +1379,13 @@ a.kpi:hover {
 }
 
 .notice.muted {
-  background: #f6f6f6;
-  border-color: #e4e4e4;
+  background: var(--notice-muted-bg);
+  border-color: var(--notice-muted-border);
+  color: var(--text-muted);
 }
 
 .todo-hint {
-  color: #6b7280;
+  color: var(--text-faint);
   font-size: 0.8rem;
   margin: 0;
 }

src/app/layout.tsx

@@ -1,4 +1,5 @@
 import type { Metadata } from "next";
+import Script from "next/script";
 import "bootstrap/dist/css/bootstrap.min.css";
 import "./globals.css";
 import { AppShell } from "../frontend/components/AppShell";
@@ -8,10 +9,33 @@ export const metadata: Metadata = {
   description: "Leistungsbilanz für elektrische Verbraucher und Stromkreislisten",
 };
 
+// Keep this key literal in sync with THEME_STORAGE_KEY in ThemeToggle.tsx.
+// It must stay inline (not imported) so it runs before hydration and never
+// flashes the wrong theme on load.
+const THEME_INIT_SCRIPT = `
+(function () {
+  try {
+    var stored = localStorage.getItem("leistungsbilanz:theme");
+    var theme =
+      stored === "dark" || stored === "light"
+        ? stored
+        : window.matchMedia("(prefers-color-scheme: dark)").matches
+          ? "dark"
+          : "light";
+    document.documentElement.setAttribute("data-bs-theme", theme);
+  } catch (error) {
+    // Storage/matchMedia unavailable: fall back to the default light theme.
+  }
+})();
+`;
+
 export default function RootLayout({ children }: Readonly<{ children: React.ReactNode }>) {
   return (
-    <html lang="de">
+    <html lang="de" suppressHydrationWarning>
       <body>
+        <Script id="theme-init" strategy="beforeInteractive">
+          {THEME_INIT_SCRIPT}
+        </Script>
         <AppShell>{children}</AppShell>
       </body>
     </html>

src/app/projects/[projectId]/page.tsx

@@ -17,13 +17,13 @@ import {
   deleteDistributionBoard,
   disconnectProjectDeviceRows,
   exportProjectTransfer,
+  getProject,
   getProjectDeviceSyncPreview,
   listCircuitLists,
   listDistributionBoards,
   listFloors,
   listGlobalDevices,
   listProjectDevices,
-  listProjects,
   listRooms,
   importProjectTransfer,
   synchronizeProjectDeviceRows,
@@ -129,7 +129,7 @@ export default function ProjectDetailPage() {
       return;
     }
     Promise.all([
-      listProjects(),
+      getProject(projectId),
       listDistributionBoards(projectId),
       listCircuitLists(projectId),
       listFloors(projectId),
@@ -138,7 +138,7 @@ export default function ProjectDetailPage() {
       listGlobalDevices(),
     ])
       .then(([
-        projects,
+        currentProject,
         distributionBoards,
         loadedCircuitLists,
         loadedFloors,
@@ -146,7 +146,6 @@ export default function ProjectDetailPage() {
         loadedProjectDevices,
         loadedGlobalDevices,
       ]) => {
-        const currentProject = projects.find((item) => item.id === projectId) ?? null;
         setProject(currentProject);
         setBoards(distributionBoards);
         setCircuitLists(loadedCircuitLists);

src/app/web-health/route.ts

@@ -0,0 +1,10 @@
+import { NextResponse } from "next/server";
+
+// Liveness probe for the web container itself. The "/health" path is
+// rewritten to the API in next.config.mjs, so it cannot answer for this
+// process. Kept as a route handler so a probe does not render a page.
+export const dynamic = "force-dynamic";
+
+export function GET() {
+  return NextResponse.json({ ok: true });
+}

src/db/migrations/0006_damp_skrulls.sql

@@ -0,0 +1,2 @@
+CREATE INDEX `circuit_device_rows_circuit_id_idx` ON `circuit_device_rows` (`circuit_id`);--> statement-breakpoint
+CREATE INDEX `circuits_section_id_idx` ON `circuits` (`section_id`);

src/db/migrations/meta/_journal.json

@@ -43,6 +43,13 @@
       "when": 1785687503453,
       "tag": "0005_stale_gorilla_man",
       "breakpoints": true
+    },
+    {
+      "idx": 6,
+      "version": "6",
+      "when": 1786043080323,
+      "tag": "0006_damp_skrulls",
+      "breakpoints": true
     }
   ]
 }

src/db/repositories/circuit-device-row.persistence.ts

@@ -43,12 +43,6 @@ export interface CircuitDeviceRowPatchInput {
   overriddenFields?: string | null;
 }
 
-export interface CircuitDeviceRowCreateInput extends CircuitDeviceRowUpdateInput {
-  circuitId: string;
-  linkedProjectDeviceId?: string;
-  sortOrder: number;
-}
-
 export function toCircuitDeviceRowUpdateValues(input: CircuitDeviceRowUpdateInput) {
   return {
     linkedProjectDeviceId: input.linkedProjectDeviceId ?? null,
@@ -105,15 +99,3 @@ export function toCircuitDeviceRowPatchValues(input: CircuitDeviceRowPatchInput)
 
   return values;
 }
-
-export function toCircuitDeviceRowCreateValues(
-  id: string,
-  input: CircuitDeviceRowCreateInput
-) {
-  return {
-    id,
-    circuitId: input.circuitId,
-    sortOrder: input.sortOrder,
-    ...toCircuitDeviceRowUpdateValues(input),
-  };
-}

src/db/repositories/circuit-project-command.repository.ts

@@ -1,4 +1,4 @@
-import { and, eq, ne } from "drizzle-orm";
+import { and, eq } from "drizzle-orm";
 import {
   assertCircuitUpdateProjectCommand,
   createCircuitUpdateProjectCommand,
@@ -21,6 +21,7 @@ import {
 import { executeProjectCommandTransactionWithAppliedForward } from "./project-command-transaction.persistence.js";
 import { resolveCircuitVoltage } from "./project-voltage.persistence.js";
 import { circuitDeviceRows } from "../schema/circuit-device-rows.js";
+import { assertEquipmentIdentifierAvailable } from "./equipment-identifier-uniqueness.persistence.js";
 
 type CircuitRow = typeof circuits.$inferSelect;
 
@@ -166,20 +167,12 @@ export class CircuitProjectCommandRepository
     ) {
       return;
     }
-    const duplicate = database
-      .select({ id: circuits.id })
-      .from(circuits)
-      .where(
-        and(
-          eq(circuits.circuitListId, circuit.circuitListId),
-          eq(circuits.equipmentIdentifier, equipmentIdentifier),
-          ne(circuits.id, circuit.id)
-        )
-      )
-      .get();
-    if (duplicate) {
-      throw new Error("Duplicate equipmentIdentifier in circuit list.");
-    }
+    assertEquipmentIdentifierAvailable(
+      database,
+      circuit.circuitListId,
+      equipmentIdentifier,
+      circuit.id
+    );
   }
 }
 

src/db/repositories/circuit-structure-project-command.repository.ts

@@ -27,6 +27,7 @@ import {
 } from "./circuit-device-row-structure.persistence.js";
 import { executeProjectCommandTransaction } from "./project-command-transaction.persistence.js";
 import { resolveCircuitVoltage } from "./project-voltage.persistence.js";
+import { assertEquipmentIdentifierAvailable } from "./equipment-identifier-uniqueness.persistence.js";
 
 export class CircuitStructureProjectCommandRepository
   implements CircuitStructureProjectCommandStore
@@ -103,24 +104,11 @@ export class CircuitStructureProjectCommandRepository
     if (existingCircuit) {
       throw new Error("Circuit id already exists.");
     }
-    const duplicateIdentifier = database
-      .select({ id: circuits.id })
-      .from(circuits)
-      .where(
-        and(
-          eq(circuits.circuitListId, snapshot.circuitListId),
-          eq(
-            circuits.equipmentIdentifier,
-            snapshot.equipmentIdentifier
-          )
-        )
-      )
-      .get();
-    if (duplicateIdentifier) {
-      throw new Error(
-        "Duplicate equipmentIdentifier in circuit list."
-      );
-    }
+    assertEquipmentIdentifierAvailable(
+      database,
+      snapshot.circuitListId,
+      snapshot.equipmentIdentifier
+    );
 
     if (snapshot.deviceRows.length > 0) {
       const rowIds = snapshot.deviceRows.map((row) => row.id);

src/db/repositories/distribution-board-component-structure-project-command.repository.ts

@@ -22,6 +22,7 @@ import { circuitSections } from "../schema/circuit-sections.js";
 import { distributionBoardComponentProtectionDevices } from "../schema/distribution-board-component-protection-devices.js";
 import { distributionBoardComponents } from "../schema/distribution-board-components.js";
 import { executeProjectCommandTransaction } from "./project-command-transaction.persistence.js";
+import { assertEquipmentIdentifierAvailable } from "./equipment-identifier-uniqueness.persistence.js";
 
 export class DistributionBoardComponentStructureProjectCommandRepository
   implements DistributionBoardComponentStructureProjectCommandStore
@@ -94,6 +95,11 @@ export class DistributionBoardComponentStructureProjectCommandRepository
     if (existing) {
       throw new Error("Distribution-board component id already exists.");
     }
+    assertEquipmentIdentifierAvailable(
+      database,
+      snapshot.component.circuitListId,
+      snapshot.component.equipmentIdentifier
+    );
     database
       .insert(distributionBoardComponents)
       .values(snapshot.component)
@@ -187,6 +193,17 @@ export class DistributionBoardComponentStructureProjectCommandRepository
         "Distribution-board component changed before update."
       );
     }
+    if (
+      target.component.equipmentIdentifier !==
+      expected.component.equipmentIdentifier
+    ) {
+      assertEquipmentIdentifierAvailable(
+        database,
+        expected.component.circuitListId,
+        target.component.equipmentIdentifier,
+        expected.component.id
+      );
+    }
     database
       .update(distributionBoardComponents)
       .set(target.component)

src/db/repositories/equipment-identifier-uniqueness.persistence.ts

@@ -0,0 +1,41 @@
+import { eq } from "drizzle-orm";
+import type { AppDatabase } from "../database-context.js";
+import { circuitListEquipmentIdentifiers } from "../schema/circuit-list-equipment-identifiers.js";
+
+export function normalizeEquipmentIdentifier(value: string): string {
+  return value.trim().toLowerCase();
+}
+
+/**
+ * The DB-level normalized unique index uses SQLite's built-in lower(),
+ * which only folds ASCII a-z and leaves German characters (Ä/Ö/Ü/ß/…)
+ * untouched, so it alone would let e.g. "Ä1" and "ä1" coexist. This check
+ * normalizes with JS's Unicode-aware toLowerCase() against every
+ * identifier already registered for the circuit list (circuits and
+ * distribution-board components share one BMK namespace via
+ * circuit_list_equipment_identifiers), catching what the DB index cannot.
+ */
+export function assertEquipmentIdentifierAvailable(
+  database: AppDatabase,
+  circuitListId: string,
+  equipmentIdentifier: string,
+  excludeOwnerId?: string
+): void {
+  const candidate = normalizeEquipmentIdentifier(equipmentIdentifier);
+  const existing = database
+    .select({
+      ownerId: circuitListEquipmentIdentifiers.ownerId,
+      equipmentIdentifier: circuitListEquipmentIdentifiers.equipmentIdentifier,
+    })
+    .from(circuitListEquipmentIdentifiers)
+    .where(eq(circuitListEquipmentIdentifiers.circuitListId, circuitListId))
+    .all();
+  const duplicate = existing.some(
+    (row) =>
+      row.ownerId !== excludeOwnerId &&
+      normalizeEquipmentIdentifier(row.equipmentIdentifier) === candidate
+  );
+  if (duplicate) {
+    throw new Error("Duplicate equipmentIdentifier in circuit list.");
+  }
+}

src/db/repositories/external-initial-import-project-command.repository.ts

@@ -212,7 +212,9 @@ function replaceExternalState(
   if (target.roomMappings.length) {
     database.insert(externalRoomMappings).values(target.roomMappings).run();
   }
-  database.insert(externalModelObjects).values(target.objects).run();
+  if (target.objects.length) {
+    database.insert(externalModelObjects).values(target.objects).run();
+  }
 }
 
 function decodeCanonicalBase64(value: string) {

src/db/repositories/external-object-new-circuit-project-command.repository.ts

@@ -32,6 +32,7 @@ import {
   loadExpectedExternalObjectTransitions,
   snapshotsEqual,
 } from "./external-object-assignment.persistence.js";
+import { assertEquipmentIdentifierAvailable } from "./equipment-identifier-uniqueness.persistence.js";
 
 export class ExternalObjectNewCircuitProjectCommandRepository
   implements ExternalObjectNewCircuitProjectCommandStore
@@ -90,12 +91,11 @@ export class ExternalObjectNewCircuitProjectCommandRepository
       .where(eq(circuits.id, circuit.id)).get()) {
       throw new Error("External circuit id already exists.");
     }
-    if (database.select({ id: circuits.id }).from(circuits).where(and(
-      eq(circuits.circuitListId, circuit.circuitListId),
-      eq(circuits.equipmentIdentifier, circuit.equipmentIdentifier)
-    )).get()) {
-      throw new Error("Duplicate equipmentIdentifier in circuit list.");
-    }
+    assertEquipmentIdentifierAvailable(
+      database,
+      circuit.circuitListId,
+      circuit.equipmentIdentifier
+    );
     if (database.select({ id: circuitDeviceRows.id }).from(circuitDeviceRows)
       .where(eq(circuitDeviceRows.id, row.id)).get()) {
       throw new Error("External device-row id already exists.");

src/db/repositories/project-device-row-sync-project-command.repository.ts

@@ -14,6 +14,7 @@ import type { AppDatabase } from "../database-context.js";
 import { circuitDeviceRows } from "../schema/circuit-device-rows.js";
 import { circuitLists } from "../schema/circuit-lists.js";
 import { circuits } from "../schema/circuits.js";
+import { externalModelObjects } from "../schema/external-model-objects.js";
 import { projectDevices } from "../schema/project-devices.js";
 import { executeProjectCommandTransaction } from "./project-command-transaction.persistence.js";
 import { updateDerivedCircuitVoltage } from "./project-voltage.persistence.js";
@@ -119,9 +120,32 @@ export class ProjectDeviceRowSyncProjectCommandRepository
     );
 
     for (const assignment of input.command.payload.rows) {
+      const values: typeof assignment.target & {
+        manualQuantity?: number;
+      } = { ...assignment.target };
+      if (assignment.target.quantity !== assignment.expected.quantity) {
+        const externalTotal = tx
+          .select({ planningValues: externalModelObjects.planningValues })
+          .from(externalModelObjects)
+          .where(
+            eq(externalModelObjects.circuitDeviceRowId, assignment.rowId)
+          )
+          .all()
+          .reduce(
+            (sum, object) => sum + object.planningValues.effectiveQuantity,
+            0
+          );
+        const manualQuantity = assignment.target.quantity - externalTotal;
+        if (manualQuantity < 0) {
+          throw new Error(
+            "Synchronized quantity is below the total quantity of linked external objects."
+          );
+        }
+        values.manualQuantity = manualQuantity;
+      }
       const updated = tx
         .update(circuitDeviceRows)
-        .set(assignment.target)
+        .set(values)
         .where(eq(circuitDeviceRows.id, assignment.rowId))
         .run();
       if (updated.changes !== 1) {

src/db/schema/circuit-device-rows.ts

@@ -1,35 +1,38 @@
-import { integer, real, sqliteTable, text } from "drizzle-orm/sqlite-core";
+import { index, integer, real, sqliteTable, text } from "drizzle-orm/sqlite-core";
 import { circuits } from "./circuits.js";
 import { projectDevices } from "./project-devices.js";
 import { rooms } from "./rooms.js";
 
-export const circuitDeviceRows = sqliteTable("circuit_device_rows", {
-  id: text("id").primaryKey(),
-  circuitId: text("circuit_id")
-    .notNull()
-    .references(() => circuits.id, { onDelete: "cascade" }),
-  linkedProjectDeviceId: text("linked_project_device_id").references(() => projectDevices.id, {
-    onDelete: "set null",
-  }),
-  sortOrder: integer("sort_order").notNull().default(0),
-  name: text("name").notNull(),
-  displayName: text("display_name").notNull(),
-  phaseType: text("phase_type"),
-  connectionKind: text("connection_kind"),
-  costGroup: text("cost_group"),
-  category: text("category"),
-  level: text("level"),
-  roomId: text("room_id").references(() => rooms.id, {
-    onDelete: "set null",
-  }),
-  roomNumberSnapshot: text("room_number_snapshot"),
-  roomNameSnapshot: text("room_name_snapshot"),
-  quantity: integer("quantity").notNull(),
-  manualQuantity: integer("manual_quantity").notNull().default(0),
-  powerPerUnit: real("power_per_unit").notNull(),
-  simultaneityFactor: real("simultaneity_factor").notNull(),
-  cosPhi: real("cos_phi"),
-  remark: text("remark"),
-  overriddenFields: text("overridden_fields"),
-});
-
+export const circuitDeviceRows = sqliteTable(
+  "circuit_device_rows",
+  {
+    id: text("id").primaryKey(),
+    circuitId: text("circuit_id")
+      .notNull()
+      .references(() => circuits.id, { onDelete: "cascade" }),
+    linkedProjectDeviceId: text("linked_project_device_id").references(() => projectDevices.id, {
+      onDelete: "set null",
+    }),
+    sortOrder: integer("sort_order").notNull().default(0),
+    name: text("name").notNull(),
+    displayName: text("display_name").notNull(),
+    phaseType: text("phase_type"),
+    connectionKind: text("connection_kind"),
+    costGroup: text("cost_group"),
+    category: text("category"),
+    level: text("level"),
+    roomId: text("room_id").references(() => rooms.id, {
+      onDelete: "set null",
+    }),
+    roomNumberSnapshot: text("room_number_snapshot"),
+    roomNameSnapshot: text("room_name_snapshot"),
+    quantity: integer("quantity").notNull(),
+    manualQuantity: integer("manual_quantity").notNull().default(0),
+    powerPerUnit: real("power_per_unit").notNull(),
+    simultaneityFactor: real("simultaneity_factor").notNull(),
+    cosPhi: real("cos_phi"),
+    remark: text("remark"),
+    overriddenFields: text("overridden_fields"),
+  },
+  (table) => [index("circuit_device_rows_circuit_id_idx").on(table.circuitId)]
+);

src/db/schema/circuits.ts

@@ -1,4 +1,4 @@
-import { integer, real, sqliteTable, text, unique } from "drizzle-orm/sqlite-core";
+import { index, integer, real, sqliteTable, text, unique } from "drizzle-orm/sqlite-core";
 import { circuitLists } from "./circuit-lists.js";
 import { circuitSections } from "./circuit-sections.js";
 
@@ -26,6 +26,9 @@ export const circuits = sqliteTable(
     isReserve: integer("is_reserve").notNull().default(0),
     remark: text("remark"),
   },
-  (table) => [unique("circuits_list_equipment_identifier_unique").on(table.circuitListId, table.equipmentIdentifier)]
+  (table) => [
+    unique("circuits_list_equipment_identifier_unique").on(table.circuitListId, table.equipmentIdentifier),
+    index("circuits_section_id_idx").on(table.sectionId),
+  ]
 );
 

src/domain/models/circuit-device-row-project-command.model.ts

@@ -144,6 +144,9 @@ function assertCircuitDeviceRowUpdateFieldValue(
     if (typeof value !== "number" || !Number.isFinite(value) || value < 0) {
       throw new Error(`${field} must be a non-negative finite number.`);
     }
+    if (field === "simultaneityFactor" && value > 1) {
+      throw new Error("simultaneityFactor must not exceed 1.");
+    }
     return;
   }
   if (field === "cosPhi") {

src/domain/models/circuit-device-row-structure-project-command.model.ts

@@ -134,6 +134,9 @@ export function assertCircuitDeviceRowInsertProjectCommand(
     row.simultaneityFactor,
     "row.simultaneityFactor"
   );
+  if (row.simultaneityFactor > 1) {
+    throw new Error("row.simultaneityFactor must not exceed 1.");
+  }
   if (row.cosPhi !== null) {
     assertFiniteNumber(row.cosPhi, "row.cosPhi");
     if (row.cosPhi <= 0) {

src/domain/models/circuit-device-row.model.ts

@@ -1,24 +0,0 @@
-export interface CircuitDeviceRow {
-  id: string;
-  circuitId: string;
-  linkedProjectDeviceId?: string;
-  sortOrder: number;
-  name: string;
-  displayName: string;
-  phaseType?: string;
-  connectionKind?: string;
-  costGroup?: string;
-  category?: string;
-  level?: string;
-  roomId?: string;
-  roomNumberSnapshot?: string;
-  roomNameSnapshot?: string;
-  quantity: number;
-  manualQuantity: number;
-  powerPerUnit: number;
-  simultaneityFactor: number;
-  cosPhi?: number;
-  remark?: string;
-  overriddenFields?: string;
-}
-

src/domain/models/circuit-protection-project-command.model.ts

@@ -71,15 +71,33 @@ export function assertCircuitProtectionUpdateProjectCommand(
   if (target !== null) {
     assertCircuitProtectionSnapshot(target, circuitId);
   }
-  if (JSON.stringify(expected) === JSON.stringify(target)) {
+  if (circuitProtectionSnapshotsEqual(expected, target)) {
     throw new Error("Circuit protection update must change state.");
   }
 }
 
+function circuitProtectionSnapshotsEqual(
+  left: CircuitProtectionSnapshot | null,
+  right: CircuitProtectionSnapshot | null
+): boolean {
+  if (left === null || right === null) {
+    return left === right;
+  }
+  return (
+    left.circuitId === right.circuitId &&
+    left.type === right.type &&
+    left.ratedCurrentA === right.ratedCurrentA &&
+    left.fuseUtilizationCategory === right.fuseUtilizationCategory &&
+    left.tripCharacteristic === right.tripCharacteristic &&
+    left.rcdType === right.rcdType &&
+    left.ratedResidualCurrentMa === right.ratedResidualCurrentMa
+  );
+}
+
 export function assertCircuitProtectionSnapshot(
   value: unknown,
   circuitId: string
-) {
+): asserts value is CircuitProtectionSnapshot {
   if (
     !isPlainObject(value) ||
     Object.keys(value).length !== 7 ||

src/domain/models/circuit-section.model.ts

@@ -1,9 +0,0 @@
-export interface CircuitSection {
-  id: string;
-  circuitListId: string;
-  key: string;
-  displayName: string;
-  prefix: string;
-  sortOrder: number;
-}
-

src/domain/models/circuit.model.ts

@@ -1,19 +0,0 @@
-export interface Circuit {
-  id: string;
-  circuitListId: string;
-  sectionId: string;
-  equipmentIdentifier: string;
-  displayName?: string;
-  sortOrder: number;
-  cableType?: string;
-  cableCrossSection?: string;
-  cableLength?: number;
-  rcdAssignment?: string;
-  terminalDesignation?: string;
-  voltage?: number;
-  controlRequirement?: string;
-  status?: string;
-  isReserve: boolean;
-  remark?: string;
-}
-

src/domain/models/project-state-snapshot.model.ts

@@ -130,7 +130,7 @@ const circuitDeviceRowSchema = z.preprocess(
     quantity: finiteNumberSchema.nonnegative(),
     manualQuantity: finiteNumberSchema.nonnegative(),
     powerPerUnit: finiteNumberSchema.nonnegative(),
-    simultaneityFactor: finiteNumberSchema.nonnegative(),
+    simultaneityFactor: finiteNumberSchema.min(0).max(1),
     cosPhi: finiteNumberSchema.positive().nullable(),
     remark: nullableStringSchema,
     overriddenFields: nullableStringSchema,

src/frontend/components/Sidebar.tsx

@@ -5,6 +5,7 @@ import { usePathname } from "next/navigation";
 import { useEffect, useState } from "react";
 import { listProjects } from "../utils/api";
 import type { ProjectDto } from "../types";
+import { ThemeToggle } from "./ThemeToggle";
 
 const PROJECT_SECTIONS = [
   { id: "verlauf", label: "Verlauf", icon: "↺" },
@@ -135,6 +136,9 @@ export function Sidebar({ isCollapsed, onToggleCollapsed }: SidebarProps) {
           </>
         )}
       </nav>
+      <div className="sidebar-footer">
+        <ThemeToggle />
+      </div>
     </aside>
   );
 }

src/frontend/components/ThemeToggle.tsx

@@ -0,0 +1,63 @@
+"use client";
+
+import { useEffect, useState } from "react";
+
+export const THEME_STORAGE_KEY = "leistungsbilanz:theme";
+
+type Theme = "light" | "dark";
+
+function applyTheme(theme: Theme) {
+  document.documentElement.setAttribute("data-bs-theme", theme);
+}
+
+export function ThemeToggle() {
+  const [theme, setTheme] = useState<Theme>("light");
+
+  // The inline script in layout.tsx already applied the persisted/system
+  // theme before hydration; read it back so the toggle starts in sync
+  // instead of flashing to "light" first.
+  useEffect(() => {
+    const current = document.documentElement.getAttribute("data-bs-theme");
+    setTheme(current === "dark" ? "dark" : "light");
+  }, []);
+
+  useEffect(() => {
+    function handleStorage(event: StorageEvent) {
+      if (
+        event.key === THEME_STORAGE_KEY &&
+        (event.newValue === "dark" || event.newValue === "light")
+      ) {
+        setTheme(event.newValue);
+        applyTheme(event.newValue);
+      }
+    }
+    window.addEventListener("storage", handleStorage);
+    return () => window.removeEventListener("storage", handleStorage);
+  }, []);
+
+  function toggleTheme() {
+    const next: Theme = theme === "dark" ? "light" : "dark";
+    setTheme(next);
+    applyTheme(next);
+    try {
+      localStorage.setItem(THEME_STORAGE_KEY, next);
+    } catch {
+      // Private browsing or disabled storage: theme still applies for
+      // this page load, just without persistence across reloads.
+    }
+  }
+
+  return (
+    <button
+      aria-pressed={theme === "dark"}
+      className="sidebar-theme-toggle"
+      onClick={toggleTheme}
+      type="button"
+    >
+      <span className="sidebar-icon" aria-hidden="true">
+        {theme === "dark" ? "☀" : "☾"}
+      </span>
+      {theme === "dark" ? "Hellmodus" : "Dunkelmodus"}
+    </button>
+  );
+}

src/frontend/components/circuit-tree-editor.tsx

@@ -268,6 +268,10 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
   const [editingCell, setEditingCell] = useState<EditingCell | null>(null);
   const [activeSectionId, setActiveSectionId] = useState<string | null>(null);
   const [isSaving, setIsSaving] = useState(false);
+  // Synchronous re-entry guard: isSaving is React state and only reflects
+  // reality after the next render, so a second click/drop fired within the
+  // same tick could otherwise race past it and double-submit a command.
+  const commandInFlightRef = useRef(false);
   const [componentEditorIntent, setComponentEditorIntent] =
     useState<StructureComponentEditorIntent | null>(null);
   const [circuitGroupEditorIntent, setCircuitGroupEditorIntent] =
@@ -723,6 +727,27 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
     );
   }, [data]);
 
+  // Clears the sidebar's target selection once it no longer resolves to a
+  // real section/circuit (e.g. deleted, moved or renumbered elsewhere)
+  // instead of silently holding a stale id after a tree reload.
+  useEffect(() => {
+    if (!data) {
+      return;
+    }
+    if (
+      targetSectionId &&
+      !data.sections.some((section) => section.id === targetSectionId)
+    ) {
+      setTargetSectionId(null);
+    }
+    if (
+      targetCircuitId &&
+      !circuitOptions.some((option) => option.id === targetCircuitId)
+    ) {
+      setTargetCircuitId(null);
+    }
+  }, [data, circuitOptions, targetSectionId, targetCircuitId]);
+
   const allCircuits = useMemo(
     () => data?.sections.flatMap((section) => section.circuits) ?? [],
     [data]
@@ -1046,6 +1071,10 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
 
   // Runs a normal command. The server records it in project-wide history.
   async function runCommand(command: HistoryCommand) {
+    if (commandInFlightRef.current) {
+      return;
+    }
+    commandInFlightRef.current = true;
     try {
       setError(null);
       setIsSaving(true);
@@ -1056,6 +1085,7 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
       await loadTree({ showLoading: false });
       setError(message);
     } finally {
+      commandInFlightRef.current = false;
       setIsSaving(false);
     }
   }
@@ -1063,6 +1093,10 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
   // Applies the next eligible project-wide history operation. Selection is only
   // a best-effort local hint; command eligibility and data changes stay server-owned.
   async function applyHistory(mode: "undo" | "redo") {
+    if (commandInFlightRef.current) {
+      return;
+    }
+    commandInFlightRef.current = true;
     try {
       setError(null);
       setHistoryBusy(true);
@@ -1088,6 +1122,7 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
       await loadTree({ showLoading: false });
       setError(message);
     } finally {
+      commandInFlightRef.current = false;
       setIsSaving(false);
       setHistoryBusy(false);
     }
@@ -1744,7 +1779,7 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
     if (!section) {
       throw new Error("Bereich wurde nicht gefunden.");
     }
-    const next = await getNextCircuitIdentifier(sectionId);
+    const next = await getNextCircuitIdentifier(projectId, sectionId);
     const sortOrder =
       section.circuits.length > 0 ? Math.max(...section.circuits.map((circuit) => circuit.sortOrder)) + 10 : 10;
     const isDeviceField = deviceFieldKeys.has(key);
@@ -1933,7 +1968,7 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
     await runCommand({
       label: "Stromkreis hinzufügen",
       redo: async () => {
-        const next = await getNextCircuitIdentifier(sectionId);
+        const next = await getNextCircuitIdentifier(projectId, sectionId);
         const sortOrder = getInsertionSortOrder(section.circuits, afterCircuitId);
         const circuit = createCircuitSnapshot({
           sectionId,
@@ -2127,7 +2162,7 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
     if (!section) {
       throw new Error("Der Zielbereich ist ungültig.");
     }
-    const next = await getNextCircuitIdentifier(sectionId);
+    const next = await getNextCircuitIdentifier(projectId, sectionId);
     const sortOrder =
       section.circuits.length > 0 ? Math.max(...section.circuits.map((circuit) => circuit.sortOrder)) + 10 : 10;
     const circuit = createCircuitSnapshot(
@@ -2538,7 +2573,7 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
     await runCommand({
       label: newCircuitLabel,
       redo: async () => {
-        const next = await getNextCircuitIdentifier(intent.sectionId);
+        const next = await getNextCircuitIdentifier(projectId, intent.sectionId);
         const sortOrder =
           intent.targetCircuitId && intent.placement
             ? getAdjacentInsertionSortOrder(
@@ -3699,6 +3734,7 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
                             type="button"
                             tabIndex={-1}
                             disabled={
+                              isSaving ||
                               !buildCircuitGroupReorderAssignments(
                                 data.sections,
                                 section.id,
@@ -3716,6 +3752,7 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
                             type="button"
                             tabIndex={-1}
                             disabled={
+                              isSaving ||
                               !buildCircuitGroupReorderAssignments(
                                 data.sections,
                                 section.id,
@@ -3733,6 +3770,7 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
                             type="button"
                             tabIndex={-1}
                             disabled={
+                              isSaving ||
                               hasActiveSortOrFilter ||
                               !section.category ||
                               !canRenumberCircuitGroups(
@@ -3758,6 +3796,7 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
                           <button
                             type="button"
                             tabIndex={-1}
+                            disabled={isSaving}
                             title={
                               canDeleteCircuitGroup(section)
                                 ? "Leere Stromkreisgruppe entfernen"
@@ -3815,13 +3854,18 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
                           >
                             Gruppen-FI hinzufügen
                           </button>
-                          <button type="button" tabIndex={-1} onClick={() => void handleAddReserveCircuit(section.id)}>
+                          <button
+                            type="button"
+                            tabIndex={-1}
+                            disabled={isSaving}
+                            onClick={() => void handleAddReserveCircuit(section.id)}
+                          >
                             Stromkreis hinzufügen
                           </button>
                           <button
                             type="button"
                             tabIndex={-1}
-                            disabled={hasActiveSortOrFilter}
+                            disabled={hasActiveSortOrFilter || isSaving}
                             onClick={() => void handleRenumberSection(section.id)}
                             title={hasActiveSortOrFilter ? "Vor der Neunummerierung Sortierung und Filter zurücksetzen." : undefined}
                           >
@@ -4426,6 +4470,7 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
                         <button
                           type="button"
                           tabIndex={-1}
+                          disabled={isSaving}
                           onClick={() => void handleAddManualDevice(row.circuit!, row.sectionId)}
                         >
                           Manuelles Gerät hinzufügen
@@ -4433,6 +4478,7 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
                         <button
                           type="button"
                           tabIndex={-1}
+                          disabled={isSaving}
                           onClick={() => void handleDeleteCircuit(row.circuit!.id)}
                         >
                           Stromkreis löschen
@@ -4440,7 +4486,7 @@ export function CircuitTreeEditor(props: { projectId: string; circuitListId: str
                       </>
                     ) : null}
                     {row.device ? (
-                      <button type="button" tabIndex={-1} onClick={() => void handleDeleteDevice(row.device!.id)}>
+                      <button type="button" tabIndex={-1} disabled={isSaving} onClick={() => void handleDeleteDevice(row.device!.id)}>
                         Gerät löschen
                       </button>
                     ) : null}

src/frontend/components/form-modal.tsx

@@ -1,6 +1,6 @@
 "use client";
 
-import React, { type FormEvent, type ReactNode } from "react";
+import React, { type FormEvent, type ReactNode, useEffect, useRef } from "react";
 
 interface FormModalProps {
   children: ReactNode;
@@ -14,6 +14,9 @@ interface FormModalProps {
   title: string;
 }
 
+const FOCUSABLE_SELECTOR =
+  'a[href], button:not([disabled]), textarea:not([disabled]), input:not([disabled]), select:not([disabled]), [tabindex]:not([tabindex="-1"])';
+
 export function FormModal({
   children,
   description,
@@ -25,11 +28,56 @@ export function FormModal({
   submitLabel,
   title,
 }: FormModalProps) {
+  const dialogRef = useRef<HTMLDivElement>(null);
+
+  // Focuses the dialog on open and returns focus to the element that
+  // triggered it on close, so keyboard users never lose their place in the
+  // grid behind the backdrop.
+  useEffect(() => {
+    const previouslyFocused = document.activeElement as HTMLElement | null;
+    const firstFocusable =
+      dialogRef.current?.querySelector<HTMLElement>(FOCUSABLE_SELECTOR);
+    firstFocusable?.focus();
+    return () => {
+      previouslyFocused?.focus();
+    };
+  }, []);
+
+  function handleKeyDown(event: React.KeyboardEvent<HTMLDivElement>) {
+    if (event.key === "Escape") {
+      if (!isSaving) {
+        event.stopPropagation();
+        onClose();
+      }
+      return;
+    }
+    if (event.key !== "Tab" || !dialogRef.current) {
+      return;
+    }
+    const focusable = Array.from(
+      dialogRef.current.querySelectorAll<HTMLElement>(FOCUSABLE_SELECTOR)
+    );
+    if (focusable.length === 0) {
+      return;
+    }
+    const first = focusable[0];
+    const last = focusable[focusable.length - 1];
+    if (event.shiftKey && document.activeElement === first) {
+      event.preventDefault();
+      last.focus();
+    } else if (!event.shiftKey && document.activeElement === last) {
+      event.preventDefault();
+      first.focus();
+    }
+  }
+
   return (
     <>
       <div
         aria-modal="true"
         className="modal fade show d-block"
+        onKeyDown={handleKeyDown}
+        ref={dialogRef}
         role="dialog"
         tabIndex={-1}
       >

src/frontend/components/project-settings-modal.tsx

@@ -7,6 +7,7 @@ import {
   distributionBoardSupplyTypes,
   type DistributionBoardSupplyType,
 } from "../../shared/constants/distribution-board";
+import { FormModal } from "./form-modal";
 
 export interface ProjectSettingsInput {
   name: string;
@@ -131,319 +132,278 @@ export function ProjectSettingsModal({
   }
 
   return (
-    <>
-      <div
-        aria-labelledby="project-settings-title"
-        aria-modal="true"
-        className="modal fade show d-block"
-        role="dialog"
-        tabIndex={-1}
-      >
-        <div className="modal-dialog modal-lg modal-dialog-centered">
-          <form className="modal-content" onSubmit={handleSubmit}>
-            <div className="modal-header">
-              <div>
-                <h2 className="modal-title fs-5" id="project-settings-title">
-                  Projekteinstellungen
-                </h2>
-                <p className="text-secondary small mb-0">
-                  Stammdaten und elektrische Standardwerte des Projekts
-                </p>
-              </div>
-              <button
-                aria-label="Schließen"
-                className="btn-close"
-                disabled={isSaving}
-                onClick={onClose}
-                type="button"
-              />
-            </div>
-            <div className="modal-body">
-              <div className="row g-3">
-                <div className="col-12">
-                  <label className="form-label" htmlFor="project-name">
-                    Projektname
-                  </label>
-                  <input
-                    autoFocus
-                    className="form-control"
-                    id="project-name"
-                    maxLength={200}
-                    onChange={(event) => setName(event.target.value)}
-                    required
-                    value={name}
-                  />
-                </div>
-                <div className="col-12 col-md-6">
-                  <label className="form-label" htmlFor="internal-project-number">
-                    Projektnummer intern
-                  </label>
-                  <input
-                    className="form-control"
-                    id="internal-project-number"
-                    maxLength={100}
-                    onChange={(event) =>
-                      setInternalProjectNumber(event.target.value)
-                    }
-                    value={internalProjectNumber}
-                  />
-                </div>
-                <div className="col-12 col-md-6">
-                  <label className="form-label" htmlFor="external-project-number">
-                    Projektnummer extern
-                  </label>
-                  <input
-                    className="form-control"
-                    id="external-project-number"
-                    maxLength={100}
-                    onChange={(event) =>
-                      setExternalProjectNumber(event.target.value)
-                    }
-                    value={externalProjectNumber}
-                  />
-                </div>
-                <div className="col-12">
-                  <fieldset>
-                    <legend className="form-label mb-1">
-                      Verwendete Netzarten
-                    </legend>
-                    <p className="form-text mt-0">
-                      Nur ausgewählte Netzarten stehen bei Verteilungen zur
-                      Auswahl. Bereits verwendete Netzarten können nicht
-                      deaktiviert werden.
-                    </p>
-                    <div className="row g-2">
-                      {distributionBoardSupplyTypes.map((supplyType) => (
-                        <div
-                          className="col-12 col-md-6"
-                          key={supplyType}
-                        >
-                          <label className="form-check">
-                            <input
-                              checked={enabledDistributionBoardSupplyTypes.includes(
-                                supplyType
-                              )}
-                              className="form-check-input"
-                              disabled={usedDistributionBoardSupplyTypes.includes(
-                                supplyType
-                              )}
-                              onChange={() => toggleSupplyType(supplyType)}
-                              type="checkbox"
-                            />
-                            <span className="form-check-label">
-                              {distributionBoardSupplyTypeLabels[supplyType]}
-                              {usedDistributionBoardSupplyTypes.includes(
-                                supplyType
-                              )
-                                ? " (in Verwendung)"
-                                : ""}
-                            </span>
-                          </label>
-                        </div>
-                      ))}
-                    </div>
-                    {enabledDistributionBoardSupplyTypes.length === 0 ? (
-                      <div className="text-danger small mt-2">
-                        Mindestens eine Netzart muss aktiviert sein.
-                      </div>
-                    ) : null}
-                  </fieldset>
-                </div>
-                <div className="col-12">
-                  <label className="form-label" htmlFor="building-owner">
-                    Bauherr
-                  </label>
-                  <input
-                    className="form-control"
-                    id="building-owner"
-                    maxLength={200}
-                    onChange={(event) => setBuildingOwner(event.target.value)}
-                    value={buildingOwner}
-                  />
-                </div>
-                <div className="col-12">
-                  <label className="form-label" htmlFor="project-description">
-                    Beschreibung
-                  </label>
-                  <textarea
-                    className="form-control"
-                    id="project-description"
-                    maxLength={2000}
-                    onChange={(event) => setDescription(event.target.value)}
-                    rows={4}
-                    value={description}
-                  />
-                </div>
-                <div className="col-12">
+    <FormModal
+      description="Stammdaten und elektrische Standardwerte des Projekts"
+      isSaving={isSaving}
+      onClose={onClose}
+      onSubmit={handleSubmit}
+      submitDisabled={!isValid}
+      submitLabel="Einstellungen speichern"
+      title="Projekteinstellungen"
+    >
+      <div className="row g-3">
+        <div className="col-12">
+          <label className="form-label" htmlFor="project-name">
+            Projektname
+          </label>
+          <input
+            autoFocus
+            className="form-control"
+            id="project-name"
+            maxLength={200}
+            onChange={(event) => setName(event.target.value)}
+            required
+            value={name}
+          />
+        </div>
+        <div className="col-12 col-md-6">
+          <label className="form-label" htmlFor="internal-project-number">
+            Projektnummer intern
+          </label>
+          <input
+            className="form-control"
+            id="internal-project-number"
+            maxLength={100}
+            onChange={(event) =>
+              setInternalProjectNumber(event.target.value)
+            }
+            value={internalProjectNumber}
+          />
+        </div>
+        <div className="col-12 col-md-6">
+          <label className="form-label" htmlFor="external-project-number">
+            Projektnummer extern
+          </label>
+          <input
+            className="form-control"
+            id="external-project-number"
+            maxLength={100}
+            onChange={(event) =>
+              setExternalProjectNumber(event.target.value)
+            }
+            value={externalProjectNumber}
+          />
+        </div>
+        <div className="col-12">
+          <fieldset>
+            <legend className="form-label mb-1">
+              Verwendete Netzarten
+            </legend>
+            <p className="form-text mt-0">
+              Nur ausgewählte Netzarten stehen bei Verteilungen zur
+              Auswahl. Bereits verwendete Netzarten können nicht
+              deaktiviert werden.
+            </p>
+            <div className="row g-2">
+              {distributionBoardSupplyTypes.map((supplyType) => (
+                <div
+                  className="col-12 col-md-6"
+                  key={supplyType}
+                >
                   <label className="form-check">
                     <input
-                      checked={isPublicBuilding}
+                      checked={enabledDistributionBoardSupplyTypes.includes(
+                        supplyType
+                      )}
                       className="form-check-input"
-                      id="public-building"
-                      onChange={(event) =>
-                        setIsPublicBuilding(event.target.checked)
-                      }
+                      disabled={usedDistributionBoardSupplyTypes.includes(
+                        supplyType
+                      )}
+                      onChange={() => toggleSupplyType(supplyType)}
                       type="checkbox"
                     />
                     <span className="form-check-label">
-                      Öffentliches Gebäude
+                      {distributionBoardSupplyTypeLabels[supplyType]}
+                      {usedDistributionBoardSupplyTypes.includes(
+                        supplyType
+                      )
+                        ? " (in Verwendung)"
+                        : ""}
                     </span>
                   </label>
-                  <div className="form-text ms-4">
-                    Wird bei der späteren Leitungsauslegung berücksichtigt,
-                    insbesondere bei der Auswahl halogenfreier Kabel und
-                    Leitungen.
-                  </div>
-                </div>
-                <div className="col-12 col-md-6">
-                  <label className="form-label" htmlFor="single-phase-voltage">
-                    Standardspannung 1-phasig [V]
-                  </label>
-                  <input
-                    className="form-control"
-                    id="single-phase-voltage"
-                    min="1"
-                    onChange={(event) =>
-                      setSinglePhaseVoltageV(event.target.value)
-                    }
-                    required
-                    type="number"
-                    value={singlePhaseVoltageV}
-                  />
-                </div>
-                <div className="col-12 col-md-6">
-                  <label className="form-label" htmlFor="three-phase-voltage">
-                    Standardspannung 3-phasig [V]
-                  </label>
-                  <input
-                    className="form-control"
-                    id="three-phase-voltage"
-                    min="1"
-                    onChange={(event) =>
-                      setThreePhaseVoltageV(event.target.value)
-                    }
-                    required
-                    type="number"
-                    value={threePhaseVoltageV}
-                  />
-                </div>
-                <div className="col-12">
-                  <hr className="my-2" />
-                  <h3 className="h6">Projekt importieren oder exportieren</h3>
-                  <p className="text-secondary small">
-                    Der Export enthält den vollständigen unterstützten
-                    Projektzustand. Beim Duplizieren bleibt dieses Projekt
-                    unverändert.
-                  </p>
-                  <button
-                    className="btn btn-outline-primary mb-3"
-                    disabled={isSaving}
-                    onClick={() => void onExport()}
-                    type="button"
-                  >
-                    Projektdatei herunterladen
-                  </button>
-                  <label className="form-label d-block" htmlFor="project-import">
-                    Projektdatei auswählen
-                  </label>
-                  <input
-                    accept=".json,application/json"
-                    className="form-control"
-                    id="project-import"
-                    onChange={(event) =>
-                      void handleTransferFile(event.target.files?.[0])
-                    }
-                    type="file"
-                  />
-                  {transferFilename ? (
-                    <div className="form-text">{transferFilename} ist bereit.</div>
-                  ) : null}
-                  {fileError ? (
-                    <div className="text-danger small mt-1">{fileError}</div>
-                  ) : null}
-                  <div className="d-flex flex-wrap gap-3 mt-3">
-                    <label className="form-check">
-                      <input
-                        checked={importMode === "duplicate"}
-                        className="form-check-input"
-                        name="import-mode"
-                        onChange={() => setImportMode("duplicate")}
-                        type="radio"
-                      />
-                      <span className="form-check-label">
-                        Als neues Projekt duplizieren
-                      </span>
-                    </label>
-                    <label className="form-check">
-                      <input
-                        checked={importMode === "replace"}
-                        className="form-check-input"
-                        name="import-mode"
-                        onChange={() => setImportMode("replace")}
-                        type="radio"
-                      />
-                      <span className="form-check-label">
-                        Dieses Projekt ersetzen
-                      </span>
-                    </label>
-                  </div>
-                  {importMode === "replace" ? (
-                    <label className="form-check mt-2">
-                      <input
-                        checked={replaceConfirmed}
-                        className="form-check-input"
-                        onChange={(event) =>
-                          setReplaceConfirmed(event.target.checked)
-                        }
-                        type="checkbox"
-                      />
-                      <span className="form-check-label text-danger">
-                        Ich bestätige, dass der aktuelle Projektstand ersetzt
-                        wird.
-                      </span>
-                    </label>
-                  ) : null}
-                  <button
-                    className="btn btn-outline-danger mt-3"
-                    disabled={
-                      isSaving ||
-                      transfer === null ||
-                      (importMode === "replace" && !replaceConfirmed)
-                    }
-                    onClick={() =>
-                      transfer === null
-                        ? undefined
-                        : void onImport(transfer, importMode)
-                    }
-                    type="button"
-                  >
-                    Projektdatei importieren
-                  </button>
                 </div>
+              ))}
+            </div>
+            {enabledDistributionBoardSupplyTypes.length === 0 ? (
+              <div className="text-danger small mt-2">
+                Mindestens eine Netzart muss aktiviert sein.
               </div>
-            </div>
-            <div className="modal-footer">
-              <button
-                className="btn btn-outline-secondary"
-                disabled={isSaving}
-                onClick={onClose}
-                type="button"
-              >
-                Abbrechen
-              </button>
-              <button
-                className="btn btn-primary"
-                disabled={isSaving || !isValid}
-                type="submit"
-              >
-                {isSaving ? "Wird gespeichert …" : "Einstellungen speichern"}
-              </button>
-            </div>
-          </form>
+            ) : null}
+          </fieldset>
+        </div>
+        <div className="col-12">
+          <label className="form-label" htmlFor="building-owner">
+            Bauherr
+          </label>
+          <input
+            className="form-control"
+            id="building-owner"
+            maxLength={200}
+            onChange={(event) => setBuildingOwner(event.target.value)}
+            value={buildingOwner}
+          />
+        </div>
+        <div className="col-12">
+          <label className="form-label" htmlFor="project-description">
+            Beschreibung
+          </label>
+          <textarea
+            className="form-control"
+            id="project-description"
+            maxLength={2000}
+            onChange={(event) => setDescription(event.target.value)}
+            rows={4}
+            value={description}
+          />
+        </div>
+        <div className="col-12">
+          <label className="form-check">
+            <input
+              checked={isPublicBuilding}
+              className="form-check-input"
+              id="public-building"
+              onChange={(event) =>
+                setIsPublicBuilding(event.target.checked)
+              }
+              type="checkbox"
+            />
+            <span className="form-check-label">
+              Öffentliches Gebäude
+            </span>
+          </label>
+          <div className="form-text ms-4">
+            Wird bei der späteren Leitungsauslegung berücksichtigt,
+            insbesondere bei der Auswahl halogenfreier Kabel und
+            Leitungen.
+          </div>
+        </div>
+        <div className="col-12 col-md-6">
+          <label className="form-label" htmlFor="single-phase-voltage">
+            Standardspannung 1-phasig [V]
+          </label>
+          <input
+            className="form-control"
+            id="single-phase-voltage"
+            min="1"
+            onChange={(event) =>
+              setSinglePhaseVoltageV(event.target.value)
+            }
+            required
+            type="number"
+            value={singlePhaseVoltageV}
+          />
+        </div>
+        <div className="col-12 col-md-6">
+          <label className="form-label" htmlFor="three-phase-voltage">
+            Standardspannung 3-phasig [V]
+          </label>
+          <input
+            className="form-control"
+            id="three-phase-voltage"
+            min="1"
+            onChange={(event) =>
+              setThreePhaseVoltageV(event.target.value)
+            }
+            required
+            type="number"
+            value={threePhaseVoltageV}
+          />
+        </div>
+        <div className="col-12">
+          <hr className="my-2" />
+          <h3 className="h6">Projekt importieren oder exportieren</h3>
+          <p className="text-secondary small">
+            Der Export enthält den vollständigen unterstützten
+            Projektzustand. Beim Duplizieren bleibt dieses Projekt
+            unverändert.
+          </p>
+          <button
+            className="btn btn-outline-primary mb-3"
+            disabled={isSaving}
+            onClick={() => void onExport()}
+            type="button"
+          >
+            Projektdatei herunterladen
+          </button>
+          <label className="form-label d-block" htmlFor="project-import">
+            Projektdatei auswählen
+          </label>
+          <input
+            accept=".json,application/json"
+            className="form-control"
+            id="project-import"
+            onChange={(event) =>
+              void handleTransferFile(event.target.files?.[0])
+            }
+            type="file"
+          />
+          {transferFilename ? (
+            <div className="form-text">{transferFilename} ist bereit.</div>
+          ) : null}
+          {fileError ? (
+            <div className="text-danger small mt-1">{fileError}</div>
+          ) : null}
+          <div className="d-flex flex-wrap gap-3 mt-3">
+            <label className="form-check">
+              <input
+                checked={importMode === "duplicate"}
+                className="form-check-input"
+                name="import-mode"
+                onChange={() => setImportMode("duplicate")}
+                type="radio"
+              />
+              <span className="form-check-label">
+                Als neues Projekt duplizieren
+              </span>
+            </label>
+            <label className="form-check">
+              <input
+                checked={importMode === "replace"}
+                className="form-check-input"
+                name="import-mode"
+                onChange={() => setImportMode("replace")}
+                type="radio"
+              />
+              <span className="form-check-label">
+                Dieses Projekt ersetzen
+              </span>
+            </label>
+          </div>
+          {importMode === "replace" ? (
+            <label className="form-check mt-2">
+              <input
+                checked={replaceConfirmed}
+                className="form-check-input"
+                onChange={(event) =>
+                  setReplaceConfirmed(event.target.checked)
+                }
+                type="checkbox"
+              />
+              <span className="form-check-label text-danger">
+                Ich bestätige, dass der aktuelle Projektstand ersetzt
+                wird.
+              </span>
+            </label>
+          ) : null}
+          <button
+            className="btn btn-outline-danger mt-3"
+            disabled={
+              isSaving ||
+              transfer === null ||
+              (importMode === "replace" && !replaceConfirmed)
+            }
+            onClick={() =>
+              transfer === null
+                ? undefined
+                : void onImport(transfer, importMode)
+            }
+            type="button"
+          >
+            Projektdatei importieren
+          </button>
         </div>
       </div>
-      <div className="modal-backdrop fade show" />
-    </>
+    </FormModal>
   );
 }
 

src/frontend/utils/api.ts

@@ -688,9 +688,9 @@ export function deleteCircuitCommand(
   );
 }
 
-export function getNextCircuitIdentifier(sectionId: string) {
+export function getNextCircuitIdentifier(projectId: string, sectionId: string) {
   return request<{ sectionId: string; nextIdentifier: string }>(
-    `/api/circuit-sections/${sectionId}/next-identifier`
+    `/api/projects/${projectId}/circuit-sections/${sectionId}/next-identifier`
   );
 }
 

src/frontend/utils/circuit-grid-model.ts

@@ -396,6 +396,16 @@ export function parseNumeric(cellKey: CellKey, draft: string): number | undefine
   if (trimmed === "") {
     return undefined;
   }
+  // A "." is ambiguous in German number entry: it could be a decimal point
+  // (English convention) or a thousands separator (e.g. "1.500" meaning
+  // one thousand five hundred). Silently guessing either way risks a wrong
+  // value entering the power balance without any visible error, so "."
+  // is rejected outright and "," is the only accepted decimal separator.
+  if (trimmed.includes(".")) {
+    throw new Error(
+      `Ungültiger Zahlenwert in ${cellKey}: Dezimalstellen mit Komma eingeben.`
+    );
+  }
   const parsed = Number(trimmed.replace(",", "."));
   if (Number.isNaN(parsed)) {
     throw new Error(`Ungültiger Zahlenwert in ${cellKey}`);

src/frontend/utils/circuit-grid-projection.ts

@@ -169,13 +169,6 @@ function makeVisibleGridRow(
   return { rowKey, rowType, sectionId, circuit, device, cells };
 }
 
-export function buildVisibleGridRows(sections: readonly CircuitTreeSectionDto[]): VisibleGridRow[] {
-  return buildVisibleGridRowsWithStructure(sections, {
-    headerComponents: [],
-    footerComponents: [],
-  });
-}
-
 export function buildVisibleGridRowsWithStructure(
   sections: readonly CircuitTreeSectionDto[],
   structure: {

src/frontend/utils/circuit-group-editing.ts

@@ -259,22 +259,28 @@ export function buildCircuitGroupRenumberPlan(
         targetGroupNumber,
         expectedPrefix,
         targetPrefix: formatGroupPrefix(category, targetGroupNumber),
-        circuits: group.circuits.map((circuit) => {
-          const circuitNumber = parseCircuitNumber(
-            circuit.equipmentIdentifier,
-            category,
-            group.groupNumber
-          );
-          return {
-            circuitId: circuit.id,
-            expectedEquipmentIdentifier: circuit.equipmentIdentifier,
-            targetEquipmentIdentifier: formatCircuitIdentifier(
+        circuits: [...group.circuits]
+          .sort(
+            (left, right) =>
+              left.sortOrder - right.sortOrder ||
+              left.id.localeCompare(right.id)
+          )
+          .map((circuit) => {
+            const circuitNumber = parseCircuitNumber(
+              circuit.equipmentIdentifier,
               category,
-              targetGroupNumber,
-              circuitNumber
-            ),
-          };
-        }),
+              group.groupNumber
+            );
+            return {
+              circuitId: circuit.id,
+              expectedEquipmentIdentifier: circuit.equipmentIdentifier,
+              targetEquipmentIdentifier: formatCircuitIdentifier(
+                category,
+                targetGroupNumber,
+                circuitNumber
+              ),
+            };
+          }),
         components: group.components.map((component) => ({
           componentId: component.id,
           expectedEquipmentIdentifier: component.equipmentIdentifier,

src/frontend/utils/circuit-section-renumber-command.ts

@@ -23,9 +23,13 @@ export function buildCircuitSectionRenumberAssignments(
         )
       )
   );
+  const orderedCircuits = [...targetSection.circuits].sort(
+    (left, right) =>
+      left.sortOrder - right.sortOrder || left.id.localeCompare(right.id)
+  );
   const assignments: CircuitSectionRenumberAssignment[] = [];
   let suffix = 1;
-  for (const circuit of targetSection.circuits) {
+  for (const circuit of orderedCircuits) {
     let targetEquipmentIdentifier = `${targetSection.prefix}${suffix}`;
     while (
       identifiersOutsideSection.has(targetEquipmentIdentifier)

src/frontend/utils/circuit-structure-projection.ts

@@ -64,7 +64,7 @@ export function buildCircuitStructureProjection(
         component,
       });
     }
-    for (const circuit of section.circuits) {
+    for (const circuit of ordered(section.circuits)) {
       rows.push({
         rowKey: `circuit-block:${circuit.id}`,
         rowType: "circuitBlock",

src/frontend/utils/project-version-history.ts

@@ -47,10 +47,24 @@ const commandTypeLabels: Record<string, string> = {
   "circuit-group.delete-subtree": "Stromkreisgruppe vollständig entfernt",
   "circuit-group.restore-subtree": "Stromkreisgruppe vollständig wiederhergestellt",
   "project-floor.insert": "Geschoss angelegt",
+  "project-floor.update": "Geschoss bearbeitet",
   "project-floor.delete": "Geschoss entfernt",
   "project-room.insert": "Raum angelegt",
+  "project-room.update": "Raum bearbeitet",
   "project-room.delete": "Raum entfernt",
   "project.restore-state": "Projektstand wiederhergestellt",
+  "circuit-protection.update": "Stromkreisschutz bearbeitet",
+  "external-csv-configuration.update": "Revit-CSV-Konfiguration bearbeitet",
+  "external-import.apply-initial": "Revit-Erstimport übernommen",
+  "external-object.assign-to-new-circuit":
+    "Externes Objekt in neuen Stromkreis übernommen",
+  "external-object.unassign-and-delete-created-circuit":
+    "Externes Objekt aus erzeugtem Stromkreis gelöst",
+  "external-object.assign-to-new-row":
+    "Externes Objekt in neue Gerätezeile übernommen",
+  "external-object.unassign-and-delete-created-row":
+    "Externes Objekt aus erzeugter Gerätezeile gelöst",
+  "external-object.update-row-assignment": "Externe Objektzuordnung geändert",
 };
 
 export function getProjectRevisionSourceLabel(

src/instrumentation-node.ts

@@ -0,0 +1,27 @@
+import { createLogger, toErrorMeta } from "./shared/logging/logger";
+
+export function registerNodeInstrumentation() {
+  const logger = createLogger("web");
+  const heartbeatIntervalMs = 5 * 60 * 1000;
+
+  logger.info("web server starting", { pid: process.pid });
+
+  process.on("uncaughtException", (error) => {
+    logger.error("uncaught exception, exiting", toErrorMeta(error));
+    process.exit(1);
+  });
+
+  process.on("unhandledRejection", (reason) => {
+    logger.error("unhandled rejection, exiting", toErrorMeta(reason));
+    process.exit(1);
+  });
+
+  setInterval(() => {
+    const memory = process.memoryUsage();
+    logger.verbose("heartbeat", {
+      uptimeSeconds: Math.round(process.uptime()),
+      rssMb: Math.round(memory.rss / 1024 / 1024),
+      heapUsedMb: Math.round(memory.heapUsed / 1024 / 1024),
+    });
+  }, heartbeatIntervalMs).unref();
+}

src/instrumentation.ts

@@ -0,0 +1,8 @@
+export async function register() {
+  if (process.env.NEXT_RUNTIME !== "nodejs") {
+    return;
+  }
+
+  const { registerNodeInstrumentation } = await import("./instrumentation-node");
+  registerNodeInstrumentation();
+}

src/proxy.ts

@@ -0,0 +1,24 @@
+import { NextResponse } from "next/server";
+import type { NextRequest } from "next/server";
+import { createLogger } from "./shared/logging/logger";
+
+const logger = createLogger("web:navigation");
+
+export function proxy(request: NextRequest) {
+  // Probes hit "/web-health" and are excluded by the matcher below. The
+  // User-Agent guard stays as a fallback for anything else that polls
+  // without one, so real navigation isn't drowned out in the logs.
+  if (request.headers.get("user-agent")) {
+    logger.info("page request", {
+      method: request.method,
+      path: request.nextUrl.pathname,
+    });
+  }
+  return NextResponse.next();
+}
+
+export const config = {
+  matcher: [
+    "/((?!_next/static|_next/image|favicon.ico|api|web-health).*)",
+  ],
+};

src/server/controllers/circuit.controller.ts

@@ -1,10 +1,21 @@
 import type { Request, Response } from "express";
 import { circuitNumberingService } from "../composition/circuit-numbering-service.js";
+import {
+  circuitListRepository,
+  circuitSectionRepository,
+} from "../composition/application-repositories.js";
 
 export async function getNextCircuitIdentifier(req: Request, res: Response) {
-  const { sectionId } = req.params;
-  if (typeof sectionId !== "string") {
-    return res.status(400).json({ error: "Invalid sectionId" });
+  const { projectId, sectionId } = req.params;
+  if (typeof projectId !== "string" || typeof sectionId !== "string") {
+    return res.status(400).json({ error: "Invalid parameters" });
+  }
+  const section = await circuitSectionRepository.findById(sectionId);
+  const list = section
+    ? await circuitListRepository.findById(projectId, section.circuitListId)
+    : null;
+  if (!section || !list) {
+    return res.status(404).json({ error: "Section not found" });
   }
   try {
     const nextIdentifier =

src/server/controllers/global-device.controller.ts

@@ -34,11 +34,12 @@ export async function updateGlobalDevice(req: Request, res: Response) {
     return res.status(400).json({ error: parsed.error.flatten() });
   }
 
-  await globalDeviceRepository.update(globalDeviceId, parsed.data);
-  const row = await globalDeviceRepository.findById(globalDeviceId);
-  if (!row) {
+  const existing = await globalDeviceRepository.findById(globalDeviceId);
+  if (!existing) {
     return res.status(404).json({ error: "Global device not found" });
   }
+  await globalDeviceRepository.update(globalDeviceId, parsed.data);
+  const row = await globalDeviceRepository.findById(globalDeviceId);
   return res.json(row);
 }
 

src/server/index.ts

@@ -1,26 +1,79 @@
 import express from "express";
-import { circuitRouter } from "./routes/circuit.routes.js";
 import { globalDeviceRouter } from "./routes/global-device.routes.js";
 import { projectDeviceRouter } from "./routes/project-device.routes.js";
 import { projectRouter } from "./routes/project.routes.js";
 import { errorMiddleware } from "./middleware/error.middleware.js";
+import { createLogger, toErrorMeta } from "../shared/logging/logger.js";
 
+const logger = createLogger("api");
 const app = express();
 const port = Number(process.env.PORT || 3000);
+const heartbeatIntervalMs = 5 * 60 * 1000;
 
 app.use(express.json({ limit: "25mb" }));
 
+app.use((req, res, next) => {
+  if (req.path === "/health") {
+    next();
+    return;
+  }
+  const startedAt = Date.now();
+  logger.debug("request started", { method: req.method, path: req.originalUrl });
+  res.on("finish", () => {
+    const meta = {
+      method: req.method,
+      path: req.originalUrl,
+      status: res.statusCode,
+      durationMs: Date.now() - startedAt,
+    };
+    if (res.statusCode >= 500) logger.error("request completed", meta);
+    else if (res.statusCode >= 400) logger.warn("request completed", meta);
+    else logger.info("request completed", meta);
+  });
+  res.on("close", () => {
+    if (!res.writableEnded) {
+      logger.warn("request aborted before response finished", {
+        method: req.method,
+        path: req.originalUrl,
+        durationMs: Date.now() - startedAt,
+      });
+    }
+  });
+  next();
+});
+
 app.get("/health", (_req, res) => {
   res.json({ ok: true });
 });
 
 app.use("/api/projects", projectRouter);
-app.use("/api", circuitRouter);
 app.use("/api/global-devices", globalDeviceRouter);
 app.use("/api/project-devices", projectDeviceRouter);
 
 app.use(errorMiddleware);
 
-app.listen(port, () => {
-  console.log(`Server running on http://localhost:${port}`);
+process.on("uncaughtException", (error) => {
+  logger.error("uncaught exception, exiting", toErrorMeta(error));
+  process.exit(1);
+});
+
+process.on("unhandledRejection", (reason) => {
+  logger.error("unhandled rejection, exiting", toErrorMeta(reason));
+  process.exit(1);
+});
+
+process.on("SIGTERM", () => logger.info("received SIGTERM"));
+process.on("SIGINT", () => logger.info("received SIGINT"));
+
+setInterval(() => {
+  const memory = process.memoryUsage();
+  logger.verbose("heartbeat", {
+    uptimeSeconds: Math.round(process.uptime()),
+    rssMb: Math.round(memory.rss / 1024 / 1024),
+    heapUsedMb: Math.round(memory.heapUsed / 1024 / 1024),
+  });
+}, heartbeatIntervalMs).unref();
+
+app.listen(port, () => {
+  logger.info("server started", { port });
 });

src/server/middleware/error.middleware.ts

@@ -1,12 +1,19 @@
 import type { NextFunction, Request, Response } from "express";
+import { createLogger, toErrorMeta } from "../../shared/logging/logger.js";
+
+const logger = createLogger("api");
 
 export function errorMiddleware(
   error: unknown,
-  _req: Request,
+  req: Request,
   res: Response,
   _next: NextFunction
 ) {
-  console.error(error);
+  logger.error("request handler threw", {
+    method: req.method,
+    path: req.originalUrl,
+    ...toErrorMeta(error),
+  });
   res.status(500).json({ error: "Internal Server Error" });
 }
 

src/server/routes/circuit.routes.ts

@@ -1,9 +0,0 @@
-import { Router } from "express";
-import {
-  getNextCircuitIdentifier,
-} from "../controllers/circuit.controller.js";
-
-export const circuitRouter = Router();
-
-circuitRouter.get("/circuit-sections/:sectionId/next-identifier", getNextCircuitIdentifier);
-

src/server/routes/project.routes.ts

@@ -16,6 +16,7 @@ import { listCircuitListsByProject } from "../controllers/circuit-list.controlle
 import { createFloor, deleteFloor, listFloorsByProject, updateFloor } from "../controllers/floor.controller.js";
 import { createRoom, deleteRoom, listRoomsByProject, updateRoom } from "../controllers/room.controller.js";
 import { getCircuitTree } from "../controllers/circuit-tree.controller.js";
+import { getNextCircuitIdentifier } from "../controllers/circuit.controller.js";
 import {
   getProjectHistory,
   listProjectRevisions,
@@ -95,6 +96,10 @@ projectRouter.delete(
 );
 projectRouter.get("/:projectId/circuit-lists", listCircuitListsByProject);
 projectRouter.get("/:projectId/circuit-lists/:circuitListId/tree", getCircuitTree);
+projectRouter.get(
+  "/:projectId/circuit-sections/:sectionId/next-identifier",
+  getNextCircuitIdentifier
+);
 projectRouter.get("/:projectId/floors", listFloorsByProject);
 projectRouter.post("/:projectId/floors", createFloor);
 projectRouter.put("/:projectId/floors/:floorId", updateFloor);

src/shared/logging/logger.ts

@@ -0,0 +1,77 @@
+export type LogLevel = "error" | "warn" | "info" | "verbose" | "debug";
+
+const LEVEL_SEVERITY: Record<LogLevel, number> = {
+  error: 0,
+  warn: 1,
+  info: 2,
+  verbose: 3,
+  debug: 4,
+};
+
+const DEFAULT_LEVEL: LogLevel = "info";
+
+export function resolveLogLevel(raw: string | undefined): LogLevel {
+  const candidate = raw?.trim().toLowerCase();
+  if (candidate && candidate in LEVEL_SEVERITY) {
+    return candidate as LogLevel;
+  }
+  return DEFAULT_LEVEL;
+}
+
+export function toErrorMeta(error: unknown): Record<string, unknown> {
+  if (error instanceof Error) {
+    return {
+      errorName: error.name,
+      errorMessage: error.message,
+      stack: error.stack,
+    };
+  }
+  return { error: typeof error === "string" ? error : JSON.stringify(error) };
+}
+
+export interface Logger {
+  error(message: string, meta?: Record<string, unknown>): void;
+  warn(message: string, meta?: Record<string, unknown>): void;
+  info(message: string, meta?: Record<string, unknown>): void;
+  verbose(message: string, meta?: Record<string, unknown>): void;
+  debug(message: string, meta?: Record<string, unknown>): void;
+}
+
+export function createLogger(
+  scope: string,
+  options?: { level?: LogLevel }
+): Logger {
+  const threshold = options?.level ?? resolveLogLevel(process.env.LOG_LEVEL);
+
+  const write = (level: LogLevel, message: string, meta?: Record<string, unknown>) => {
+    if (LEVEL_SEVERITY[level] > LEVEL_SEVERITY[threshold]) {
+      return;
+    }
+    const timestamp = new Date().toISOString();
+    let line: string;
+    try {
+      line = JSON.stringify({ timestamp, level, scope, message, ...meta });
+    } catch {
+      line = JSON.stringify({
+        timestamp,
+        level,
+        scope,
+        message,
+        logError: "failed to serialize log metadata",
+      });
+    }
+    if (level === "error" || level === "warn") {
+      console.error(line);
+    } else {
+      console.log(line);
+    }
+  };
+
+  return {
+    error: (message, meta) => write("error", message, meta),
+    warn: (message, meta) => write("warn", message, meta),
+    info: (message, meta) => write("info", message, meta),
+    verbose: (message, meta) => write("verbose", message, meta),
+    debug: (message, meta) => write("debug", message, meta),
+  };
+}

src/shared/validation/external-csv.schemas.ts

@@ -1,5 +1,10 @@
 import { z } from "zod";
 
+// Base64 length of the 18 MiB transport limit documented for CSV uploads
+// (18 * 1024 * 1024 bytes, evenly divisible by 3, so ceil(N/3)*4 with no
+// padding). Keep in sync with the controller's raw byte-length check.
+export const MAX_CSV_CONTENT_BASE64_LENGTH = 25_165_824;
+
 export const updateExternalCsvConfigurationSchema = z
   .object({
     expectedRevision: z.number().int().nonnegative(),
@@ -10,7 +15,7 @@ export const updateExternalCsvConfigurationSchema = z
 export const previewExternalCsvSchema = z
   .object({
     fileName: z.string().trim().min(1).max(255),
-    contentBase64: z.string().min(1).max(24_000_000),
+    contentBase64: z.string().min(1).max(MAX_CSV_CONTENT_BASE64_LENGTH),
   })
   .strict();
 
@@ -21,7 +26,7 @@ export const applyExternalInitialImportSchema = z.object({
   expectedConfigurationVersion: z.number().int().positive(),
   expectedSha256: z.string().regex(/^[a-f0-9]{64}$/),
   fileName: z.string().trim().min(1).max(255),
-  contentBase64: z.string().min(1).max(24_000_000),
+  contentBase64: z.string().min(1).max(MAX_CSV_CONTENT_BASE64_LENGTH),
   sourceName: z.string().trim().min(1).max(200),
   roomDecisions: z.array(z.object({
     sourceRoomKey: z.string().trim().min(1),

src/shared/validation/global-device.schemas.ts

@@ -1,15 +1,15 @@
 import { z } from "zod";
 
 export const createGlobalDeviceSchema = z.object({
-  name: z.string().min(1),
-  displayName: z.string().min(1),
-  category: z.string().optional(),
+  name: z.string().min(1).max(200),
+  displayName: z.string().min(1).max(200),
+  category: z.string().max(100).optional(),
   quantity: z.number().min(0),
   installedPowerPerUnitKw: z.number().min(0),
   demandFactor: z.number().min(0).max(1),
   phaseCount: z.union([z.literal(1), z.literal(3)]),
   powerFactor: z.number().min(0).max(1).optional(),
-  note: z.string().optional(),
+  note: z.string().max(2000).optional(),
 }).strict();
 
 export const updateGlobalDeviceSchema = createGlobalDeviceSchema;

src/shared/validation/project-device.schemas.ts

@@ -4,16 +4,16 @@ import { expectedProjectRevisionSchema } from "./project-command.schemas.js";
 import { circuitGroupCategories } from "../constants/circuit-group.js";
 
 export const createProjectDeviceSchema = z.object({
-  name: z.string().min(1),
-  displayName: z.string().min(1),
-  connectionKind: z.string().optional(),
-  costGroup: z.string().optional(),
+  name: z.string().min(1).max(200),
+  displayName: z.string().min(1).max(200),
+  connectionKind: z.string().max(100).optional(),
+  costGroup: z.string().max(100).optional(),
   category: z.enum(circuitGroupCategories),
   quantity: z.number().min(0),
   powerPerUnit: z.number().min(0),
   simultaneityFactor: z.number().min(0).max(1),
   cosPhi: z.number().min(0).max(1).optional(),
-  remark: z.string().optional(),
+  remark: z.string().max(2000).optional(),
 }).strict();
 
 export const updateProjectDeviceSchema = createProjectDeviceSchema;

src/shared/validation/project-structure.schemas.ts

@@ -36,7 +36,7 @@ export const updateProjectSettingsSchema = z
 export const createDistributionBoardSchema = z
   .object({
     expectedRevision: expectedProjectRevisionSchema,
-    name: z.string().trim().min(1),
+    name: z.string().trim().min(1).max(200),
     floorId: z.string().trim().min(1).nullable(),
     supplyType: z.enum(distributionBoardSupplyTypes),
   })
@@ -67,7 +67,7 @@ export const deleteDistributionBoardSchema = z
 export const createFloorSchema = z
   .object({
     expectedRevision: expectedProjectRevisionSchema,
-    name: z.string().trim().min(1),
+    name: z.string().trim().min(1).max(200),
   })
   .strict();
 
@@ -83,8 +83,8 @@ export const createRoomSchema = z
   .object({
     expectedRevision: expectedProjectRevisionSchema,
     floorId: z.string().trim().min(1).optional(),
-    roomNumber: z.string().trim().min(1),
-    roomName: z.string().trim().min(1),
+    roomNumber: z.string().trim().min(1).max(50),
+    roomName: z.string().trim().min(1).max(200),
   })
   .strict();
 
@@ -92,8 +92,8 @@ export const updateRoomSchema = z
   .object({
     expectedRevision: expectedProjectRevisionSchema,
     floorId: z.string().trim().min(1).nullable(),
-    roomNumber: z.string().trim().min(1),
-    roomName: z.string().trim().min(1),
+    roomNumber: z.string().trim().min(1).max(50),
+    roomName: z.string().trim().min(1).max(200),
   })
   .strict();
 

tests/circuit-grid-model.test.ts

@@ -187,12 +187,25 @@ describe("circuit grid model", () => {
   });
 
   it("parses numeric drafts and rejects invalid values", () => {
-    assert.equal(parseNumeric("quantity", " 2.5 "), 2.5);
+    assert.equal(parseNumeric("quantity", " 1500 "), 1500);
     assert.equal(parseNumeric("powerPerUnit", " 1,25 "), 1.25);
     assert.equal(parseNumeric("quantity", ""), undefined);
     assert.throws(() => parseNumeric("quantity", "two"), /Ungültiger Zahlenwert/);
   });
 
+  it("rejects a dot instead of silently misreading it as a thousands separator", () => {
+    // "1.500" typed with German thousands-separator intent (meaning 1500)
+    // must never silently become 1.5 — it must fail loudly instead.
+    assert.throws(
+      () => parseNumeric("cableLength", "1.500"),
+      /Dezimalstellen mit Komma eingeben/
+    );
+    assert.throws(
+      () => parseNumeric("powerPerUnit", "2.5"),
+      /Dezimalstellen mit Komma eingeben/
+    );
+  });
+
   it("builds nullable circuit command patches from grid drafts", () => {
     assert.deepEqual(buildCircuitEditPatch("voltage", ""), {
       voltage: null,

tests/circuit-grid-projection.test.ts

@@ -1,7 +1,6 @@
 import assert from "node:assert/strict";
 import { describe, it } from "node:test";
 import {
-  buildVisibleGridRows,
   buildVisibleGridRowsWithStructure,
   filterAndSortCircuitSections,
   getDistinctFilterValues,
@@ -101,7 +100,7 @@ describe("circuit grid projection", () => {
     ];
 
     const projectedSections = filterAndSortCircuitSections(emptySections, {}, null);
-    const rows = buildVisibleGridRows(projectedSections);
+    const rows = buildVisibleGridRowsWithStructure(projectedSections, { headerComponents: [], footerComponents: [] });
 
     assert.equal(projectedSections.length, 2);
     assert.deepEqual(
@@ -150,7 +149,7 @@ describe("circuit grid projection", () => {
   });
 
   it("builds the compact, grouped, reserve and placeholder row shapes", () => {
-    const rows = buildVisibleGridRows(sections);
+    const rows = buildVisibleGridRowsWithStructure(sections, { headerComponents: [], footerComponents: [] });
 
     assert.deepEqual(rows.map((row) => row.rowType), [
       "section",
@@ -191,7 +190,7 @@ describe("circuit grid projection", () => {
         },
       })),
     }));
-    const rows = buildVisibleGridRows(protectedSections);
+    const rows = buildVisibleGridRowsWithStructure(protectedSections, { headerComponents: [], footerComponents: [] });
     const protectionValue = (rowType: string) =>
       rows
         .find((row) => row.rowType === rowType)

tests/circuit-structure-project-command.repository.test.ts

@@ -580,4 +580,43 @@ describe("circuit structure project-command repository", () => {
       fixture.context.close();
     }
   });
+
+  it("rejects a BMK that differs from an existing one only by German umlaut casing", () => {
+    const fixture = createTestDatabase();
+    try {
+      const store = new CircuitStructureProjectCommandRepository(
+        fixture.context.db
+      );
+      store.execute({
+        projectId: "project-1",
+        expectedRevision: 0,
+        source: "user",
+        command: createCircuitInsertProjectCommand(
+          createCircuitSnapshot(fixture, {
+            id: "umlaut-original",
+            equipmentIdentifier: "-1F9Ä",
+            deviceRows: [],
+          })
+        ),
+      });
+      assert.throws(
+        () =>
+          store.execute({
+            projectId: "project-1",
+            expectedRevision: 1,
+            source: "user",
+            command: createCircuitInsertProjectCommand(
+              createCircuitSnapshot(fixture, {
+                id: "umlaut-duplicate",
+                equipmentIdentifier: "-1f9ä",
+                deviceRows: [],
+              })
+            ),
+          }),
+        /Duplicate equipmentIdentifier in circuit list\./
+      );
+    } finally {
+      fixture.context.close();
+    }
+  });
 });

tests/circuit.controller.test.ts

@@ -0,0 +1,100 @@
+import assert from "node:assert/strict";
+import { describe, it } from "node:test";
+import { getNextCircuitIdentifier } from "../src/server/controllers/circuit.controller.js";
+import {
+  circuitListRepository,
+  circuitSectionRepository,
+} from "../src/server/composition/application-repositories.js";
+import { circuitNumberingService } from "../src/server/composition/circuit-numbering-service.js";
+
+function createMockResponse() {
+  let statusCode = 200;
+  let body: unknown;
+  return {
+    response: {
+      status(code: number) {
+        statusCode = code;
+        return this;
+      },
+      json(value: unknown) {
+        body = value;
+        return this;
+      },
+    },
+    getStatusCode: () => statusCode,
+    getBody: () => body,
+  };
+}
+
+describe("circuit controller", () => {
+  it("returns the next identifier when the section belongs to the project", async () => {
+    const originals = {
+      findSection: circuitSectionRepository.findById,
+      findList: circuitListRepository.findById,
+      getNextIdentifier: circuitNumberingService.getNextIdentifier,
+    };
+    circuitSectionRepository.findById = async () =>
+      ({ id: "section-1", circuitListId: "list-1", prefix: "-1F" }) as never;
+    circuitListRepository.findById = async (projectId: string, circuitListId: string) =>
+      projectId === "project-1" && circuitListId === "list-1"
+        ? ({ id: "list-1", projectId: "project-1" } as never)
+        : null;
+    circuitNumberingService.getNextIdentifier = async () => "-1F3";
+    const mock = createMockResponse();
+    try {
+      await getNextCircuitIdentifier(
+        { params: { projectId: "project-1", sectionId: "section-1" } } as never,
+        mock.response as never
+      );
+    } finally {
+      circuitSectionRepository.findById = originals.findSection;
+      circuitListRepository.findById = originals.findList;
+      circuitNumberingService.getNextIdentifier = originals.getNextIdentifier;
+    }
+    assert.deepEqual(mock.getBody(), {
+      sectionId: "section-1",
+      nextIdentifier: "-1F3",
+    });
+  });
+
+  it("returns 404 instead of leaking numbering state for a section from another project", async () => {
+    const originals = {
+      findSection: circuitSectionRepository.findById,
+      findList: circuitListRepository.findById,
+    };
+    circuitSectionRepository.findById = async () =>
+      ({ id: "section-1", circuitListId: "list-1", prefix: "-1F" }) as never;
+    // The section exists, but its circuit list does not belong to the requesting project.
+    circuitListRepository.findById = async () => null;
+    const mock = createMockResponse();
+    try {
+      await getNextCircuitIdentifier(
+        { params: { projectId: "foreign-project", sectionId: "section-1" } } as never,
+        mock.response as never
+      );
+    } finally {
+      circuitSectionRepository.findById = originals.findSection;
+      circuitListRepository.findById = originals.findList;
+    }
+    assert.equal(mock.getStatusCode(), 404);
+    assert.deepEqual(mock.getBody(), { error: "Section not found" });
+  });
+
+  it("returns 404 for a section that does not exist", async () => {
+    const originals = {
+      findSection: circuitSectionRepository.findById,
+    };
+    circuitSectionRepository.findById = async () => null;
+    const mock = createMockResponse();
+    try {
+      await getNextCircuitIdentifier(
+        { params: { projectId: "project-1", sectionId: "missing" } } as never,
+        mock.response as never
+      );
+    } finally {
+      circuitSectionRepository.findById = originals.findSection;
+    }
+    assert.equal(mock.getStatusCode(), 404);
+    assert.deepEqual(mock.getBody(), { error: "Section not found" });
+  });
+});

tests/distribution-board-component-structure-project-command.repository.test.ts

@@ -580,7 +580,7 @@ describe("distribution-board component structure project command", () => {
                 snapshot
               ),
           }),
-        /UNIQUE constraint failed/
+        /Duplicate equipmentIdentifier in circuit list\./
       );
       assert.equal(
         context.db.select().from(projectRevisions).all().length,

tests/external-csv-api-contract.test.ts

@@ -2,6 +2,7 @@ import assert from "node:assert/strict";
 import { describe, it } from "node:test";
 import {
   applyExternalInitialImportSchema,
+  MAX_CSV_CONTENT_BASE64_LENGTH,
   planExternalInitialImportSchema,
   previewExternalCsvSchema,
   updateExternalCsvConfigurationSchema,
@@ -74,7 +75,7 @@ describe("external CSV API contracts", () => {
     assert.equal(
       previewExternalCsvSchema.safeParse({
         fileName: "revit.csv",
-        contentBase64: "a".repeat(24_000_001),
+        contentBase64: "a".repeat(MAX_CSV_CONTENT_BASE64_LENGTH + 1),
       }).success,
       false
     );

tests/external-initial-import-project-command.repository.test.ts

@@ -195,6 +195,30 @@ describe("external initial import project command", () => {
     }
   });
 
+  it("rejects a target state with zero classified objects before writing anything", () => {
+    // assertPopulatedInitialState requires at least one object, so a CSV
+    // that classified none must be rejected at command construction, not
+    // reach the persistence layer's bulk insert.
+    const { context, configuration } = createTestContext();
+    try {
+      const target: ExternalModelStateSnapshot = {
+        ...initialState(configuration),
+        roomMappings: [],
+        objects: [],
+      };
+      assert.throws(
+        () =>
+          createExternalInitialImportProjectCommand(
+            createEmptyExternalModelState(),
+            target
+          ),
+        /at least one object/
+      );
+    } finally {
+      context.close();
+    }
+  });
+
   it("rejects changed state, checksum drift and row assignment", () => {
     const { context, configuration } = createTestContext();
     try {

tests/logger.test.ts

@@ -0,0 +1,83 @@
+import assert from "node:assert/strict";
+import { describe, it } from "node:test";
+import { createLogger, resolveLogLevel } from "../src/shared/logging/logger.js";
+
+describe("resolveLogLevel", () => {
+  it("defaults to info for missing or unknown values", () => {
+    assert.equal(resolveLogLevel(undefined), "info");
+    assert.equal(resolveLogLevel(""), "info");
+    assert.equal(resolveLogLevel("nonsense"), "info");
+  });
+
+  it("accepts known levels case-insensitively", () => {
+    assert.equal(resolveLogLevel("DEBUG"), "debug");
+    assert.equal(resolveLogLevel(" verbose "), "verbose");
+    assert.equal(resolveLogLevel("warn"), "warn");
+  });
+});
+
+describe("createLogger", () => {
+  it("suppresses levels below the configured threshold", () => {
+    const infoLines: string[] = [];
+    const originalLog = console.log;
+    console.log = (line: string) => {
+      infoLines.push(line);
+    };
+    try {
+      const logger = createLogger("test", { level: "warn" });
+      logger.info("should not appear");
+      logger.debug("should not appear");
+      logger.verbose("should not appear");
+    } finally {
+      console.log = originalLog;
+    }
+    assert.equal(infoLines.length, 0);
+  });
+
+  it("emits enabled levels as structured JSON with scope and meta", () => {
+    const errorLines: string[] = [];
+    const originalError = console.error;
+    console.error = (line: string) => {
+      errorLines.push(line);
+    };
+    try {
+      const logger = createLogger("test", { level: "warn" });
+      logger.warn("something happened", { code: 42 });
+    } finally {
+      console.error = originalError;
+    }
+    assert.equal(errorLines.length, 1);
+    const parsed = JSON.parse(errorLines[0]);
+    assert.equal(parsed.level, "warn");
+    assert.equal(parsed.scope, "test");
+    assert.equal(parsed.message, "something happened");
+    assert.equal(parsed.code, 42);
+    assert.equal(typeof parsed.timestamp, "string");
+  });
+
+  it("routes debug/verbose/info to console.log and error/warn to console.error", () => {
+    const logLines: string[] = [];
+    const errorLines: string[] = [];
+    const originalLog = console.log;
+    const originalError = console.error;
+    console.log = (line: string) => {
+      logLines.push(line);
+    };
+    console.error = (line: string) => {
+      errorLines.push(line);
+    };
+    try {
+      const logger = createLogger("test", { level: "debug" });
+      logger.debug("d");
+      logger.verbose("v");
+      logger.info("i");
+      logger.warn("w");
+      logger.error("e");
+    } finally {
+      console.log = originalLog;
+      console.error = originalError;
+    }
+    assert.equal(logLines.length, 3);
+    assert.equal(errorLines.length, 2);
+  });
+});

tests/project-command.model.test.ts

@@ -209,6 +209,13 @@ describe("circuit device-row update project commands", () => {
         }),
       /non-negative/
     );
+    assert.throws(
+      () =>
+        createCircuitDeviceRowUpdateProjectCommand("row-1", {
+          simultaneityFactor: 1.5,
+        }),
+      /must not exceed 1/
+    );
   });
 });
 
@@ -508,6 +515,14 @@ describe("circuit device-row structure project commands", () => {
         }),
       /must not be negative/
     );
+    assert.throws(
+      () =>
+        createCircuitDeviceRowInsertProjectCommand({
+          ...row,
+          simultaneityFactor: 1.5,
+        }),
+      /must not exceed 1/
+    );
     assert.throws(
       () => createCircuitDeviceRowDeleteProjectCommand("", "circuit-1"),
       /rowId/

tests/project-device-row-sync-project-command.repository.test.ts

@@ -13,9 +13,13 @@ import { ProjectHistoryRepository } from "../src/db/repositories/project-history
 import { circuitDeviceRows } from "../src/db/schema/circuit-device-rows.js";
 import { circuitSections } from "../src/db/schema/circuit-sections.js";
 import { circuits } from "../src/db/schema/circuits.js";
+import { externalImportBatches } from "../src/db/schema/external-import-batches.js";
+import { externalModelObjects } from "../src/db/schema/external-model-objects.js";
+import { externalModelSources } from "../src/db/schema/external-model-sources.js";
 import { projectDevices } from "../src/db/schema/project-devices.js";
 import { projectRevisions } from "../src/db/schema/project-revisions.js";
 import { projects } from "../src/db/schema/projects.js";
+import { externalCsvTestConfiguration } from "./fixtures/revit-csv-fixtures.js";
 import {
   createProjectDeviceRowSyncProjectCommand,
   type ProjectDeviceSyncRowSnapshot,
@@ -163,6 +167,79 @@ function getRow(context: DatabaseContext, rowId: string) {
   return row;
 }
 
+function linkExternalObject(
+  context: DatabaseContext,
+  rowId: string,
+  effectiveQuantity: number
+) {
+  context.db
+    .insert(externalModelSources)
+    .values({
+      id: "source-1",
+      projectId: "project-1",
+      name: "Revit",
+      sourceType: "revit_csv",
+    })
+    .run();
+  context.db
+    .insert(externalImportBatches)
+    .values({
+      id: "batch-1",
+      projectId: "project-1",
+      sourceId: "source-1",
+      importKind: "initial",
+      importedAtIso: "2026-08-02T16:00:00.000Z",
+      fileName: "revit.csv",
+      sha256: "a".repeat(64),
+      appliedProjectRevision: 0,
+      configurationVersion: 1,
+      configurationSnapshot: externalCsvTestConfiguration,
+      originalBytes: Buffer.from("test"),
+      document: { delimiter: ";", encoding: "utf-8", headers: [], rows: [] },
+    })
+    .run();
+  context.db
+    .insert(externalModelObjects)
+    .values({
+      id: "object-1",
+      projectId: "project-1",
+      sourceId: "source-1",
+      ifcGuid: "ifc-1",
+      lastSeenImportBatchId: "batch-1",
+      lastAcceptedImportBatchId: "batch-1",
+      acceptedSourceValues: {
+        rowNumber: 2,
+        roomNumber: "101",
+        roomName: "Büro",
+        familyAndType: "Leuchte: Standard",
+        selectionMarker: "Leuchte",
+        circuitIdentifier: "-1F1",
+        power: "30",
+        quantity: String(effectiveQuantity),
+        additionalSourceValues: {},
+      },
+      planningValues: {
+        displayName: "Leuchte",
+        internalDeviceType: "luminaire",
+        category: "single_phase",
+        connectionKind: "fixed",
+        effectiveQuantity,
+        powerPerUnitW: 30,
+        simultaneityFactor: 1,
+        cosPhi: null,
+        costGroup: null,
+        remark: null,
+      },
+      overriddenFields: [],
+      externalRoomMappingId: null,
+      distributionBoardId: null,
+      linkedProjectDeviceId: null,
+      circuitDeviceRowId: rowId,
+      presenceStatus: "present",
+    })
+    .run();
+}
+
 function snapshot(
   context: DatabaseContext,
   rowId: string
@@ -474,6 +551,112 @@ describe("project-device row sync project-command repository", () => {
     }
   });
 
+  it("keeps manualQuantity from exceeding quantity when a synced quantity shrinks", () => {
+    const fixture = createTestDatabase();
+    try {
+      fixture.context.db
+        .update(circuitDeviceRows)
+        .set({ quantity: 5, manualQuantity: 5 })
+        .where(eq(circuitDeviceRows.id, "row-1"))
+        .run();
+      const store = new ProjectDeviceRowSyncProjectCommandRepository(
+        fixture.context.db
+      );
+      const expected = snapshot(fixture.context, "row-1");
+      store.execute({
+        projectId: "project-1",
+        expectedRevision: 0,
+        source: "user",
+        command: createProjectDeviceRowSyncProjectCommand(
+          "project-device-1",
+          "synchronize",
+          [
+            {
+              rowId: "row-1",
+              expected,
+              target: { ...expected, quantity: 2 },
+            },
+          ]
+        ),
+      });
+      const row = getRow(fixture.context, "row-1");
+      assert.equal(row.quantity, 2);
+      assert.equal(row.manualQuantity, 2);
+    } finally {
+      fixture.context.close();
+    }
+  });
+
+  it("subtracts linked external objects when a synced quantity shrinks", () => {
+    const fixture = createTestDatabase();
+    try {
+      fixture.context.db
+        .update(circuitDeviceRows)
+        .set({ quantity: 5, manualQuantity: 2 })
+        .where(eq(circuitDeviceRows.id, "row-1"))
+        .run();
+      linkExternalObject(fixture.context, "row-1", 3);
+      const store = new ProjectDeviceRowSyncProjectCommandRepository(
+        fixture.context.db
+      );
+      const expected = snapshot(fixture.context, "row-1");
+      store.execute({
+        projectId: "project-1",
+        expectedRevision: 0,
+        source: "user",
+        command: createProjectDeviceRowSyncProjectCommand(
+          "project-device-1",
+          "synchronize",
+          [{ rowId: "row-1", expected, target: { ...expected, quantity: 4 } }]
+        ),
+      });
+      const row = getRow(fixture.context, "row-1");
+      assert.equal(row.quantity, 4);
+      assert.equal(row.manualQuantity, 1);
+    } finally {
+      fixture.context.close();
+    }
+  });
+
+  it("rejects a synced quantity below the linked external total", () => {
+    const fixture = createTestDatabase();
+    try {
+      fixture.context.db
+        .update(circuitDeviceRows)
+        .set({ quantity: 5, manualQuantity: 2 })
+        .where(eq(circuitDeviceRows.id, "row-1"))
+        .run();
+      linkExternalObject(fixture.context, "row-1", 3);
+      const store = new ProjectDeviceRowSyncProjectCommandRepository(
+        fixture.context.db
+      );
+      const expected = snapshot(fixture.context, "row-1");
+      assert.throws(
+        () =>
+          store.execute({
+            projectId: "project-1",
+            expectedRevision: 0,
+            source: "user",
+            command: createProjectDeviceRowSyncProjectCommand(
+              "project-device-1",
+              "synchronize",
+              [{ rowId: "row-1", expected, target: { ...expected, quantity: 2 } }]
+            ),
+          }),
+        /below the total quantity of linked external objects/
+      );
+      const row = getRow(fixture.context, "row-1");
+      assert.equal(row.quantity, 5);
+      assert.equal(row.manualQuantity, 2);
+      assert.equal(
+        fixture.context.db.select().from(projectRevisions).all().length,
+        0
+      );
+    } finally {
+      fixture.context.close();
+    }
+  });
+
   it("rolls back synchronized rows for a stale project revision", () => {
     const fixture = createTestDatabase();
     try {

tests/project-version-history.test.ts

@@ -191,6 +191,32 @@ describe("project version history presentation", () => {
       ),
       "Stromkreisgruppe vollständig wiederhergestellt"
     );
+    assert.equal(
+      getProjectRevisionDescription(
+        revision(16, { commandType: "circuit-protection.update" })
+      ),
+      "Stromkreisschutz bearbeitet"
+    );
+    assert.equal(
+      getProjectRevisionDescription(
+        revision(17, { commandType: "project-floor.update" })
+      ),
+      "Geschoss bearbeitet"
+    );
+    assert.equal(
+      getProjectRevisionDescription(
+        revision(18, { commandType: "project-room.update" })
+      ),
+      "Raum bearbeitet"
+    );
+    assert.equal(
+      getProjectRevisionDescription(
+        revision(19, {
+          commandType: "external-object.update-row-assignment",
+        })
+      ),
+      "Externe Objektzuordnung geändert"
+    );
     assert.equal(getProjectSnapshotKindLabel("named"), "Benannt");
     assert.equal(
       getProjectSnapshotKindLabel("automatic"),

tsconfig.json

@@ -11,5 +11,11 @@
     "resolveJsonModule": true
   },
   "include": ["src/**/*.ts"],
-  "exclude": ["node_modules", "dist"]
+  "exclude": [
+    "node_modules",
+    "dist",
+    "src/proxy.ts",
+    "src/instrumentation.ts",
+    "src/instrumentation-node.ts"
+  ]
 }

tsconfig.next.json

@@ -18,6 +18,9 @@
     "src/app/**/*.tsx",
     "src/frontend/**/*.ts",
     "src/frontend/**/*.tsx",
+    "src/proxy.ts",
+    "src/instrumentation.ts",
+    "src/instrumentation-node.ts",
     ".next/types/**/*.ts"
   ],
   "exclude": ["node_modules", "dist"]

tsconfig.scripts.json

@@ -5,5 +5,11 @@
     "rootDir": "."
   },
   "include": ["scripts/**/*.ts", "src/**/*.ts"],
-  "exclude": ["node_modules", "dist"]
+  "exclude": [
+    "node_modules",
+    "dist",
+    "src/proxy.ts",
+    "src/instrumentation.ts",
+    "src/instrumentation-node.ts"
+  ]
 }