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/components/layout/AppShell.tsx

@@ -6,7 +6,9 @@ import { PluginToolbar } from './PluginToolbar';
 import { MessageSidebar } from './MessageSidebar';
 import { ToastContainer } from '@/components/ui/Toast';
 import { useAIContext } from '@/hooks/useAIContext';
+import { useAIUIControl } from '@/hooks/useAIUIControl';
 import { PluginRegistry } from '@/components/plugins/PluginRegistry';
+import { AIUIControlIndicator } from '@/components/ai-ui-control/AIUIControlIndicator';
 
 export function AppShell() {
   const location = useLocation();
@@ -14,6 +16,9 @@ export function AppShell() {
   // Track context for AI Proactive suggestions
   useAIContext();
 
+  // AI UI Control — WebSocket-based UI control from AI agents (Phase 4)
+  useAIUIControl();
+
   // Hide message sidebar on the AI Assistant page itself
   const showMessageSidebar = !location.pathname.startsWith('/ai-assistant');
 
@@ -38,6 +43,7 @@ export function AppShell() {
       </div>
       {/* Message Sidebar — full height, right of TopBar and Toolbar */}
       {showMessageSidebar && <MessageSidebar />}
+      <AIUIControlIndicator />
       <ToastContainer />
     </div>
   );