Persist project locations

docs/circuit-list-editor-api.md

@@ -190,6 +190,23 @@ returns HTTP `409` with `PROJECT_HISTORY_OPERATION_UNAVAILABLE`.
     structure; Redo restores the same ids
   - stale revisions return `409 PROJECT_REVISION_CONFLICT`
 
+### Project Floors and Rooms
+
+- `POST /projects/:projectId/floors`
+  - body: `{ "name": "EG", "expectedRevision": 13 }`
+  - executes `project-floor.insert` with a stable floor id
+  - response: `{ "floor": { ... }, "revision": { ... }, "history": { ... } }`
+- `POST /projects/:projectId/rooms`
+  - body:
+    `{ "floorId": "floor_1", "roomNumber": "001", "roomName": "Technik", "expectedRevision": 14 }`
+  - executes `project-room.insert` with a stable room id; `floorId` is optional
+    and must belong to the project when present
+  - response: `{ "room": { ... }, "revision": { ... }, "history": { ... } }`
+- Persistent Undo removes only unchanged, unreferenced records. A floor with
+  assigned rooms and a room referenced by device rows or retained upgrade data
+  are rejected instead of silently clearing foreign keys.
+- Stale revisions return `409 PROJECT_REVISION_CONFLICT`.
+
 ### Tree Endpoint
 
 - `GET /projects/:projectId/circuit-lists/:circuitListId/tree`