Add section renumber history

docs/circuit-list-editor-api.md

@@ -28,13 +28,14 @@ The public dispatcher currently supports `circuit.update`, `circuit.insert`,
 `circuit-device-row.insert`, `circuit-device-row.delete` and
 `circuit-device-row.move` plus
 `circuit-device-row.move-with-new-circuit` and `circuit.reorder-section`, all
-with schema version `1`. Other command types are rejected. Insert commands
-contain the complete entity or circuit block with stable ids; delete commands
-include the expected parent identity. Circuit snapshots contain zero, one or
-multiple complete device rows. Move commands contain each row's expected and
-target circuit plus its exact expected and target sort order. This makes
-deletion and moves undoable without generating replacement identities or
-renumbering circuits. The editor does not consume these endpoints yet.
+with `circuit.renumber-section`, all with schema version `1`. Other command
+types are rejected. Insert commands contain the complete entity or circuit
+block with stable ids; delete commands include the expected parent identity.
+Circuit snapshots contain zero, one or multiple complete device rows. Move
+commands contain each row's expected and target circuit plus its exact expected
+and target sort order. This makes deletion and moves undoable without
+generating replacement identities or renumbering circuits. The editor does not
+consume these endpoints yet.
 
 `circuit-device-row.move` targets existing circuits in the same circuit list.
 `circuit-device-row.move-with-new-circuit` atomically creates exactly one
@@ -48,6 +49,13 @@ in the section. Each assignment records the expected and target `sortOrder`.
 The command and its inverse change no circuit field other than `sortOrder`;
 equipment identifiers and complete device-row blocks remain unchanged.
 
+`circuit.renumber-section` is an explicit operation requiring one assignment
+for every circuit in the section. Assignments contain expected and target
+equipment identifiers. The store rejects stale values, duplicate targets and
+targets occupied by other sections, then applies swaps through collision-safe
+temporary identifiers. Undo restores the exact prior identifiers; sort
+positions and device rows remain unchanged.
+
 Example:
 
 ```json

docs/current-architecture.md

@@ -99,8 +99,11 @@ Felder und vollständiger Zeilenbestand unverändert sind.
 `circuit.reorder-section` speichert die erwartete und neue Sortierposition
 jedes Stromkreises eines vollständigen Abschnitts. Forward, Undo und Redo
 ändern ausschließlich `sortOrder`; Stromkreisblöcke, Gerätezeilen und BMKs
-bleiben unverändert. Neunummerierung und Synchronisierung müssen vor der
-Frontend-Umstellung noch als persistente Commands modelliert werden.
+bleiben unverändert. `circuit.renumber-section` bildet die getrennte,
+ausdrücklich ausgelöste Neunummerierung ab. Es speichert alle erwarteten und
+neuen BMKs des Abschnitts, löst Tauschkollisionen über temporäre Werte und
+ändert weder Sortierung noch Gerätezeilen. Synchronisierung muss vor der
+Frontend-Umstellung noch als persistentes Command modelliert werden.
 
 ## Projektgeräte
 

docs/project-history-and-external-model-architecture.md

@@ -189,13 +189,16 @@ Completed foundation:
 - `circuit.reorder-section` requires the complete section circuit set and
   stores exact expected/target sort positions; its inverse changes no
   equipment identifier and never splits a circuit block
+- `circuit.renumber-section` is the separate explicit renumber operation; it
+  stores every expected/target equipment identifier, uses collision-safe
+  temporary values and restores the exact prior identifiers on undo
 
 Remaining constraints before completing persistent history:
 
 - extend the concrete project-scoped command union and executors beyond the
   Circuit field/insert/delete and CircuitDeviceRow
-  field/insert/delete/move plus section-reorder slices; the generic versioned
-  command envelope is complete
+  field/insert/delete/move plus section-reorder/renumber slices; the generic
+  versioned command envelope is complete
 - route the remaining structural, synchronization and destructive domain
   writes through the shared command, revision and stack transaction boundary
 - replace the session-local frontend command stack only after server-side

docs/spec/07-implementation-phases-todo.md

@@ -403,6 +403,9 @@ Implemented foundation:
   unchanged generated circuit, without renumbering
 - complete section reorders persist every expected and target circuit
   `sortOrder`; undo/redo changes neither equipment identifiers nor device rows
+- explicit section renumber commands persist every expected and target
+  equipment identifier, apply swaps collision-safely and restore exact prior
+  identifiers without changing sort positions or device rows
 - revision metadata, change-set payloads and the project counter are committed
   in one SQLite transaction
 - a stale expected revision produces no history writes