feat: Implement sync manager and file watcher for automated playlist synchronization

app/utils/playlist_merge.py

@@ -159,8 +159,21 @@ def _read_text_if_exists(path: str) -> tuple[str, bool]:
 def _save_playlist_to_folder(filename: str, paths: Sequence[str], folder: str) -> str:
     _ensure_test_dir(folder)
     file_path = os.path.join(folder, filename)
+    
+    new_content = save_paths(paths)
+    
+    # Check if content has changed before writing to avoid triggering unnecessary file events
+    if os.path.exists(file_path):
+        try:
+            with open(file_path, "r", encoding="utf-8") as f:
+                current_content = f.read()
+            if current_content == new_content:
+                return file_path
+        except OSError:
+            pass
+
     with open(file_path, "w", encoding="utf-8") as file:
-        file.write(save_paths(paths))
+        file.write(new_content)
     return file_path