feat: Implement offline library management with IndexedDB support

- Added `useOfflineLibrary` hook for managing offline library state and synchronization.
- Created `OfflineLibraryManager` class for handling IndexedDB operations and syncing with Navidrome API.
- Implemented methods for retrieving and storing albums, artists, songs, and playlists.
- Added support for offline favorites management (star/unstar).
- Implemented playlist creation, updating, and deletion functionalities.
- Added search functionality for offline data.
- Created a manifest file for PWA support with icons and shortcuts.
- Added service worker file for caching and offline capabilities.

next.config.mjs

@@ -45,7 +45,7 @@ const nextConfig = {
           },
           {
             key: 'Content-Security-Policy',
-            value: "default-src 'self'; script-src 'self'",
+            value: "default-src 'self' *; connect-src 'self' *; script-src 'self'",
           },
         ],
       },