fix: convert str to path first (#388)

Co-authored-by: Spoked <Spoked@localhost>

backend/program/libraries/symlink.py

@@ -48,7 +48,7 @@ def run(self) -> MediaItem:
 def process_items(directory: Path, item_class, item_type: str, is_anime: bool = False):
     """Process items in the given directory and yield MediaItem instances."""
     items = [
-        (root, files[0])
+        (Path(root), files[0])
         for root, _, files
         in os.walk(directory)
         if files