feat: add ImageLoadingService for downloading series artwork

- Create ImageLoadingService that downloads poster.jpg, fanart.jpg, and
  logo.png from TMDB when anime is added or during scheduler rescan
- Integrate into BackgroundLoaderService._load_nfo_and_images() to trigger
  image downloads when new anime is added
- Add image_scan_after_rescan config option to scheduler (default: true)
- Add _run_image_scan() to scheduler rescan flow, processing series in
  batches of 10 to respect TMDB rate limits
- Fix SearchResult model missing folder, snippet, and score fields
- Update background_loader tests to match new image loading behavior

src/server/services/background_loader_service.py

@@ -497,24 +497,55 @@ class BackgroundLoaderService:
     
     async def _load_nfo_and_images(self, task: SeriesLoadingTask, db: Any) -> bool:
         """Load NFO file and images for a series.
-        
-        Note: NFO service has been removed. This method now just marks
-        progress as False since NFO handling moved to server layer.
-        
+
+        Downloads poster.jpg, fanart.jpg, and logo.png from TMDB
+        using the ImageLoadingService.
+
         Args:
             task: The loading task
             db: Database session
-            
+
         Returns:
-            bool: Always False since NFO service removed
+            bool: True if any images were loaded, False otherwise
         """
         task.status = LoadingStatus.LOADING_NFO
-        await self._broadcast_status(task, "NFO loading disabled...")
-        
-        task.progress["nfo"] = False
-        task.progress["logo"] = False
-        task.progress["images"] = False
-        return False
+        await self._broadcast_status(task, "Loading images...")
+
+        try:
+            from src.server.nfo.tmdb_client import get_tmdb_client
+            from src.server.services.image_loading_service import (
+                init_image_loading_service,
+            )
+
+            tmdb_client = get_tmdb_client()
+            image_service = init_image_loading_service(tmdb_client)
+
+            result = await image_service.load_series_images(
+                key=task.key,
+                folder=task.folder,
+                anime_directory=self.series_app.directory_to_search,
+                db=db,
+            )
+
+            task.progress["nfo"] = True  # NFO was already created earlier in the flow
+            task.progress["logo"] = result.get("logo", False)
+            task.progress["images"] = result.get("poster", False) and result.get("fanart", False)
+
+            logger.info(
+                "Images loaded for series %s: poster=%s fanart=%s logo=%s",
+                task.key,
+                result.get("poster", False),
+                result.get("fanart", False),
+                result.get("logo", False),
+            )
+            return True
+
+        except Exception as e:
+            logger.warning("Failed to load images for series %s: %s", task.key, e)
+            task.progress["nfo"] = True
+            task.progress["logo"] = False
+            task.progress["images"] = False
+            return False
     
     async def _scan_missing_episodes(self, task: SeriesLoadingTask, db: Any) -> None:
         """Scan for missing episodes after NFO creation.