fix and update

apps/frontend/lib/api.ts

@@ -494,6 +494,19 @@ export async function refreshAuthSession(): Promise<RefreshSessionResponse> {
   return response.json() as Promise<RefreshSessionResponse>;
 }
 
+export async function syncFedcmSession(accessToken: string) {
+  if (typeof window === 'undefined' || !accessToken.trim()) return;
+  try {
+    await fetch(`${getApiUrl()}/fedcm/session/sync`, {
+      method: 'POST',
+      headers: { Authorization: `Bearer ${accessToken.trim()}` },
+      credentials: 'include'
+    });
+  } catch {
+    // фоновая синхронизация FedCM cookie
+  }
+}
+
 async function trySilentTokenRefresh(): Promise<RefreshSessionResponse | null> {
   try {
     const refreshed = await refreshAuthSession();