feat(backend): sync limiters on agent connect

Implemented full sync of speed limit configurations when an Agent connects via WebSocket. This ensures that even fresh or restarted agents receive the necessary limiter configurations.

go-backend/internal/ws/server.go

@@ -71,6 +71,8 @@ type Server struct {
 	nodes   map[int64]*nodeSession
 	byConn  map[*websocket.Conn]*nodeSession
 	pending map[string]pendingRequest
+
+	OnNodeConnected func(nodeID int64)
 }
 
 func NewServer(repo *sqlite.Repository, jwtSecret string) *Server {
@@ -164,6 +166,10 @@ func (s *Server) handleNode(w http.ResponseWriter, r *http.Request, nodeID int64
 	_ = s.repo.UpdateNodeOnline(nodeID, 1, version, httpVal, tlsVal, socksVal)
 	s.broadcastStatus(nodeID, 1)
 
+	if s.OnNodeConnected != nil {
+		go s.OnNodeConnected(nodeID)
+	}
+
 	defer func() {
 		needOfflineBroadcast := false
 		s.mu.Lock()