refactor(playlists_page): move playlist header widget to playlist widgets folder for better organization

Author: gokadzev

lib/screens/playlist_page.dart

@@ -41,7 +41,7 @@ import 'package:musify/utilities/sort_utils.dart';
 import 'package:musify/utilities/utils.dart';
 import 'package:musify/widgets/edit_playlist_dialog.dart';
 import 'package:musify/widgets/playlist_cube.dart';
-import 'package:musify/widgets/playlist_header.dart';
+import 'package:musify/widgets/playlists_page/playlist_header.dart';
 import 'package:musify/widgets/playlists_page/playlist_search_bar.dart';
 import 'package:musify/widgets/playlists_page/shuffle_play_button.dart';
 import 'package:musify/widgets/song_bar.dart';

lib/screens/user_songs_page.dart

@@ -29,7 +29,7 @@ import 'package:musify/services/settings_manager.dart';
 import 'package:musify/utilities/flutter_toast.dart';
 import 'package:musify/utilities/utils.dart';
 import 'package:musify/widgets/playlist_cube.dart';
-import 'package:musify/widgets/playlist_header.dart';
+import 'package:musify/widgets/playlists_page/playlist_header.dart';
 import 'package:musify/widgets/playlists_page/playlist_search_bar.dart';
 import 'package:musify/widgets/playlists_page/shuffle_play_button.dart';
 import 'package:musify/widgets/song_bar.dart';