feat: board-first orchestration with Gateway Bridge, live-update, and flow-board

- GatewayBridgeController: MCP-artiger Kommando-Adapter für Agent-zu-Backend
- TaskBridgeService + LiveUpdateService: SSE Live-Sync + Bridge-Kommandos
- FlowBoard.vue: Board-first orchestration dashboard panel
- live-sync.ts store + live.ts service: SSE-basierte Live-Updates
- Nullability-Warnung in HealthController.cs gefixt
- nginx.conf: SSE-Proxy + CORS für Bridge-Endpunkte
- .gitignore: pnpm/corepack local caches ausgeschlossen
- docs: architecture-board-first-orchestration.md hinzugefügt
- README: Backend Bridge API dokumentiert

frontend/src/views/NotificationsView.vue

@@ -2,10 +2,12 @@
 import { onMounted, onUnmounted, computed } from 'vue'
 import { useRouter } from 'vue-router'
 import { useNotificationStore } from '../stores/notifications'
+import { useLiveSyncStore } from '../stores/live-sync'
 import { Bell, BellOff, CheckCheck, ChevronRight } from '@lucide/vue'
 
 const store = useNotificationStore()
 const router = useRouter()
+const liveSyncStore = useLiveSyncStore()
 
 const sortedNotifications = computed(() => {
   return [...store.notifications].sort(
@@ -53,10 +55,12 @@ function onNotificationClick(n: { id: string, taskId: string | null }) {
 
 onMounted(() => {
   store.startListPolling()
+  liveSyncStore.connect()
 })
 
 onUnmounted(() => {
   store.stopListPolling()
+  liveSyncStore.disconnect()
 })
 </script>