Refactor various components to improve code clarity and maintainability. Update ListUsersQueryHandler to utilize UserListFilter for parameter handling. Refactor BumperSpecFactory and related classes to encapsulate input parameters into dedicated records, enhancing readability. Adjust MediaAsset and Slot classes to streamline content updates with new content models. Improve BumperRenderBackgroundService and MediaProcessingBackgroundService to use MediaReadyInfo for asset readiness, ensuring consistent parameter management across the application.

frontend/src/features/admin/images/ImageGallery.tsx

@@ -142,9 +142,15 @@ export function GalleryBrowser({
       </div>
 
       <div className="mt-3 max-h-[55vh] overflow-y-auto">
-        {isLoading ? (
+        {isLoading && (
           <p className="py-6 text-center text-sm text-muted-foreground">{t('common.loading')}</p>
-        ) : images && images.length > 0 ? (
+        )}
+        {!isLoading && sorted.length === 0 && (
+          <p className="py-6 text-center text-sm text-muted-foreground">
+            {t('admin.gallery.empty')}
+          </p>
+        )}
+        {!isLoading && sorted.length > 0 && (
           <div className="grid grid-cols-3 gap-3 sm:grid-cols-4 md:grid-cols-5">
             {sorted.map((img) => (
               <div key={img.id} className="group relative">
@@ -175,10 +181,6 @@ export function GalleryBrowser({
               </div>
             ))}
           </div>
-        ) : (
-          <p className="py-6 text-center text-sm text-muted-foreground">
-            {t('admin.gallery.empty')}
-          </p>
         )}
       </div>
     </>