Fix general settings route and req.user references

- Update frontend settings service to use correct /api/admin/settings/general route
- Fix all req.user to req.admin references in adminSettings.js
- Ensures settings can be saved without authentication errors

frontend/src/pages/GalleryPage.tsx

@@ -10,14 +10,14 @@ import { GalleryView } from '../components/gallery';
 import { analyticsService } from '../services/analytics.service';
 
 export const GalleryPage: React.FC = () => {
-  const { slug } = useParams<{ slug: string }>();
+  const { slug, token } = useParams<{ slug: string; token?: string }>();
   const { isAuthenticated, login, event } = useGalleryAuth();
   const [password, setPassword] = useState('');
   const [isLoggingIn, setIsLoggingIn] = useState(false);
   const [loginError, setLoginError] = useState<string | null>(null);
 
   // Fetch gallery info (public data)
-  const { data: galleryInfo, isLoading: isLoadingInfo, error: infoError } = useGalleryInfo(slug!);
+  const { data: galleryInfo, isLoading: isLoadingInfo, error: infoError } = useGalleryInfo(slug!, token);
 
   // Calculate days until expiration
   const daysUntilExpiration = galleryInfo