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/de.json

@@ -77,7 +77,8 @@
     "status": "Status",
     "role": "Rolle",
     "active": "Aktiv",
-    "inactive": "Inaktiv"
+    "inactive": "Inaktiv",
+    "dismiss": "Schließen"
   },
   "dashboard": {
     "title": "Dashboard",
@@ -891,5 +892,17 @@
     "empty": "Keine Änderungshistorie vorhanden",
     "changes": "Änderungen",
     "fieldsChanged": "Felder geändert"
+  },
+  "ai": {
+    "uiControl": {
+      "active": "KI steuert die UI",
+      "executing": "KI führt Aktion aus",
+      "navigate": "Navigation",
+      "filter": "Filter setzen",
+      "openContact": "Kontakt öffnen",
+      "modal": "Dialog öffnen",
+      "tab": "Tab wechseln",
+      "settings": "Einstellungen ändern"
+    }
   }
 }