fix: wire admin photo feedback filters into grid query (#293)

The Has Likes / Has Favorites / Has Comments checkboxes in the admin
Event > Photos tab updated local state but never affected the visible
photo grid, because the feedbackFilters state was only wired to the
export menu and the backend /admin/photos/:eventId/photos endpoint had
no support for these params.

Fixes:
- backend/src/routes/adminPhotos.js: extend GET /:eventId/photos to
  accept has_likes, has_favorites, has_comments, min_rating, and logic
  (AND/OR) query params and apply them via where-clause groups using
  the existing denormalized like_count/favorite_count/comment_count/
  average_rating columns.
- frontend/src/services/photos.service.ts: add hasLikes, hasFavorites,
  hasComments, minRating, logic to the PhotoFilters interface and
  append them as query params in getEventPhotos.
- frontend/src/pages/admin/EventDetailsPage.tsx: merge feedbackFilters
  into combinedPhotoFilters (via useMemo) and key the admin-event-photos
  query on it, so toggling any checkbox refetches with the new params.

Verified end-to-end against local Docker: seeded event with a known
feedback distribution and confirmed
- Has Likes → 4 photos
- Has Favorites → 3 photos
- Likes AND Favorites → 1 photo
- Likes OR Favorites → 6 photos
- Has Comments → 2 photos
- network requests carry the exact query params

frontend/src/services/photos.service.ts

@@ -32,6 +32,11 @@ export interface PhotoFilters {
   search?: string;
   sort?: 'date' | 'name' | 'size' | 'rating';
   order?: 'asc' | 'desc';
+  hasLikes?: boolean;
+  hasFavorites?: boolean;
+  hasComments?: boolean;
+  minRating?: number | null;
+  logic?: 'AND' | 'OR';
 }
 
 class PhotosService {
@@ -47,6 +52,13 @@ class PhotosService {
       if (filters.search) params.append('search', filters.search);
       if (filters.sort) params.append('sort', filters.sort);
       if (filters.order) params.append('order', filters.order);
+      if (filters.hasLikes) params.append('has_likes', 'true');
+      if (filters.hasFavorites) params.append('has_favorites', 'true');
+      if (filters.hasComments) params.append('has_comments', 'true');
+      if (filters.minRating !== undefined && filters.minRating !== null) {
+        params.append('min_rating', filters.minRating.toString());
+      }
+      if (filters.logic) params.append('logic', filters.logic);
     }
     
     const queryString = params.toString();