feat(lyrics): keep the screen awake while viewing lyrics

lib/models/settings.g.dart

@@ -67,6 +67,7 @@ AppSettings _$AppSettingsFromJson(Map<String, dynamic> json) => AppSettings(
       json['extensionVerificationBrowserMode'] as String? ?? 'in_app_first',
   locale: json['locale'] as String? ?? 'system',
   lyricsMode: json['lyricsMode'] as String? ?? 'embed',
+  keepScreenOnLyrics: json['keepScreenOnLyrics'] as bool? ?? true,
   autoConvertDownloads: json['autoConvertDownloads'] as bool? ?? false,
   redownloadFakeHiRes: json['redownloadFakeHiRes'] as bool? ?? false,
   autoConvertFormat: json['autoConvertFormat'] as String? ?? 'mp3',
@@ -164,6 +165,7 @@ Map<String, dynamic> _$AppSettingsToJson(
   'extensionVerificationBrowserMode': instance.extensionVerificationBrowserMode,
   'locale': instance.locale,
   'lyricsMode': instance.lyricsMode,
+  'keepScreenOnLyrics': instance.keepScreenOnLyrics,
   'autoConvertDownloads': instance.autoConvertDownloads,
   'redownloadFakeHiRes': instance.redownloadFakeHiRes,
   'autoConvertFormat': instance.autoConvertFormat,