fix and update

apps/frontend/app/family/page.tsx

@@ -10,6 +10,7 @@ import { Button } from '@/components/ui/button';
 import { Input } from '@/components/ui/input';
 import { useRequireAuth } from '@/hooks/use-require-auth';
 import { apiFetch, FamilyGroup, fetchFamilyGroups, getApiErrorMessage } from '@/lib/api';
+import { defaultFamilyGroupName } from '@/lib/family-defaults';
 
 export default function FamilyPage() {
   const router = useRouter();
@@ -17,9 +18,15 @@ export default function FamilyPage() {
   const { isReady, isPinLocked } = useRequireAuth();
   const { showToast } = useToast();
   const [groups, setGroups] = useState<FamilyGroup[]>([]);
-  const [name, setName] = useState('Моя семья');
+  const [name, setName] = useState('');
   const [creating, setCreating] = useState(false);
 
+  useEffect(() => {
+    if (user?.displayName) {
+      setName(defaultFamilyGroupName(user.displayName));
+    }
+  }, [user?.displayName]);
+
   useEffect(() => {
     if (!user || !token || isPinLocked) return;
     fetchFamilyGroups(user.id, token)
@@ -63,7 +70,7 @@ export default function FamilyPage() {
 
       <div className="mt-8 flex gap-3">
         <Input value={name} onChange={(event) => setName(event.target.value)} placeholder="Название семьи" />
-        <Button onClick={() => void createGroup()} disabled={creating}>
+        <Button onClick={() => void createGroup()} disabled={creating || !name.trim()}>
           {creating ? 'Создаём...' : (<><Plus className="h-4 w-4" />Создать</>)}
         </Button>
       </div>