Initialize backend before search server

The backend's Init() must be called before search.Init() because
buildIndexes() calls storage.GetResourceStats() which requires
the database connection to be established.

Previously, backend.Init() was called by ResourceServer.Init()
through the Lifecycle hooks, but now search.Init() runs before
ResourceServer is created.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

pkg/storage/unified/sql/server.go

@@ -159,6 +159,13 @@ func NewResourceServer(opts ServerOptions) (resource.ResourceServer, resource.Se
 		}
 	}
 
+	// Initialize the backend before creating search server (it needs the DB connection)
+	if serverOptions.Lifecycle != nil {
+		if err := serverOptions.Lifecycle.Init(context.Background()); err != nil {
+			return nil, nil, fmt.Errorf("failed to initialize backend: %w", err)
+		}
+	}
+
 	search, err := resource.NewSearchServer(opts.SearchOptions, serverOptions.Backend, opts.AccessClient, nil, opts.IndexMetrics, opts.OwnsIndexFn)
 	if err != nil {
 		return nil, nil, fmt.Errorf("failed to initialize search: %w", err)