fix(backend): sync limiter on association instead of connection

Reverted the full sync on connection hook. Instead, ensureLimiterOnNode is called within syncForwardServices to push limiter configuration immediately before pushing the service configuration that references it.

go-backend/internal/http/handler/handler.go

@@ -62,13 +62,11 @@ type flowItem struct {
 }
 
 func New(repo *sqlite.Repository, jwtSecret string) *Handler {
-	h := &Handler{
+	return &Handler{
 		repo:      repo,
 		jwtSecret: jwtSecret,
 		wsServer:  ws.NewServer(repo, jwtSecret),
 	}
-	h.wsServer.OnNodeConnected = h.onNodeConnected
-	return h
 }
 
 func (h *Handler) WebSocketHandler() http.Handler {