Phase 4: KI-UI-Steuerung — AI agent UI control via WebSocket

- New ai_ui_control plugin: WS endpoint /ws/ai-ui-control, REST API (POST /command, GET /command/{id}/status, GET /online-users)
- UI-Command-Protocol: 6 command types (navigate, filter, open_contact, modal, tab, settings) with Pydantic schemas
- WebSocket manager: per-user connections, command delivery, feedback storage, stale cleanup
- Frontend useAIUIControl hook: WS client with auto-reconnect, command dispatch, feedback sending
- aiUIControlStore: Zustand store for command state, active modal/tab, pending filter/settings
- AIUIControlIndicator: visual KI indication (Bot icon, toast, pulse animation)
- ContactDetail integration: syncs activeTab and personModalOpen from AI control store
- AppShell integration: useAIUIControl hook + AIUIControlIndicator
- i18n keys for DE/EN
- 18 Vitest tests: command protocol, store actions, feedback, visual indication
- TSC: 0 new errors (only 2 pre-existing Dms.tsx errors)

frontend/src/i18n/locales/en.json

@@ -77,7 +77,8 @@
     "status": "Status",
     "role": "Role",
     "active": "Active",
-    "inactive": "Inactive"
+    "inactive": "Inactive",
+    "dismiss": "Dismiss"
   },
   "dashboard": {
     "title": "Dashboard",
@@ -891,5 +892,17 @@
     "empty": "No change history available",
     "changes": "Changes",
     "fieldsChanged": "fields changed"
+  },
+  "ai": {
+    "uiControl": {
+      "active": "AI is controlling the UI",
+      "executing": "AI is executing action",
+      "navigate": "Navigation",
+      "filter": "Apply filter",
+      "openContact": "Open contact",
+      "modal": "Open dialog",
+      "tab": "Switch tab",
+      "settings": "Change settings"
+    }
   }
 }