Initial scaffold: React+TS+Vite frontend, FastAPI backend, config system

backend/routes/ws_routes.py

@@ -0,0 +1,19 @@
+from fastapi import APIRouter, WebSocket, WebSocketDisconnect
+from mqtt_bridge import register_ws_client, unregister_ws_client
+
+router = APIRouter()
+
+
+@router.websocket("/api/ws/events")
+async def websocket_events(ws: WebSocket):
+    await ws.accept()
+    register_ws_client(ws)
+    try:
+        while True:
+            # Keep connection alive, handle client messages if needed
+            data = await ws.receive_text()
+            # Client can send ping/keepalive
+    except WebSocketDisconnect:
+        pass
+    finally:
+        unregister_ws_client(ws)