feat(download): add automatic lossy conversion

lib/l10n/app_localizations.dart

@@ -2764,6 +2764,60 @@ abstract class AppLocalizations {
   /// **'Lossy Format'**
   String get downloadLossyFormat;
 
+  /// Toggle for automatic post-download audio conversion
+  ///
+  /// In en, this message translates to:
+  /// **'Auto-convert after download'**
+  String get downloadAutoConvert;
+
+  /// Explanation of safe automatic post-download conversion
+  ///
+  /// In en, this message translates to:
+  /// **'Convert completed downloads to a smaller lossy format. The original is replaced only after conversion succeeds.'**
+  String get downloadAutoConvertSubtitle;
+
+  /// Automatic conversion output format setting
+  ///
+  /// In en, this message translates to:
+  /// **'Output format'**
+  String get downloadAutoConvertFormat;
+
+  /// Automatic conversion format picker explanation
+  ///
+  /// In en, this message translates to:
+  /// **'Choose the lossy format used for newly completed downloads.'**
+  String get downloadAutoConvertFormatSubtitle;
+
+  /// Automatic conversion bitrate setting
+  ///
+  /// In en, this message translates to:
+  /// **'Output quality'**
+  String get downloadAutoConvertBitrate;
+
+  /// Automatic conversion bitrate picker explanation
+  ///
+  /// In en, this message translates to:
+  /// **'Higher bitrates preserve more detail but create larger files.'**
+  String get downloadAutoConvertBitrateSubtitle;
+
+  /// MP3 automatic conversion option description
+  ///
+  /// In en, this message translates to:
+  /// **'Best compatibility across players and devices'**
+  String get downloadAutoConvertMp3Subtitle;
+
+  /// M4A AAC automatic conversion option description
+  ///
+  /// In en, this message translates to:
+  /// **'Efficient AAC audio in an M4A container'**
+  String get downloadAutoConvertM4aSubtitle;
+
+  /// Opus automatic conversion option description
+  ///
+  /// In en, this message translates to:
+  /// **'Best efficiency for modern players'**
+  String get downloadAutoConvertOpusSubtitle;
+
   /// Title of the lossy format picker bottom sheet
   ///
   /// In en, this message translates to:

lib/l10n/app_localizations_de.dart

@@ -1515,6 +1515,39 @@ class AppLocalizationsDe extends AppLocalizations {
   @override
   String get downloadLossyFormat => 'Verlustbehaftetes Format';
 
+  @override
+  String get downloadAutoConvert => 'Auto-convert after download';
+
+  @override
+  String get downloadAutoConvertSubtitle =>
+      'Convert completed downloads to a smaller lossy format. The original is replaced only after conversion succeeds.';
+
+  @override
+  String get downloadAutoConvertFormat => 'Output format';
+
+  @override
+  String get downloadAutoConvertFormatSubtitle =>
+      'Choose the lossy format used for newly completed downloads.';
+
+  @override
+  String get downloadAutoConvertBitrate => 'Output quality';
+
+  @override
+  String get downloadAutoConvertBitrateSubtitle =>
+      'Higher bitrates preserve more detail but create larger files.';
+
+  @override
+  String get downloadAutoConvertMp3Subtitle =>
+      'Best compatibility across players and devices';
+
+  @override
+  String get downloadAutoConvertM4aSubtitle =>
+      'Efficient AAC audio in an M4A container';
+
+  @override
+  String get downloadAutoConvertOpusSubtitle =>
+      'Best efficiency for modern players';
+
   @override
   String get downloadLossy320Format => 'Verlustbehaftetes 320kbps-Format';
 

lib/l10n/app_localizations_en.dart

@@ -1494,6 +1494,39 @@ class AppLocalizationsEn extends AppLocalizations {
   @override
   String get downloadLossyFormat => 'Lossy Format';
 
+  @override
+  String get downloadAutoConvert => 'Auto-convert after download';
+
+  @override
+  String get downloadAutoConvertSubtitle =>
+      'Convert completed downloads to a smaller lossy format. The original is replaced only after conversion succeeds.';
+
+  @override
+  String get downloadAutoConvertFormat => 'Output format';
+
+  @override
+  String get downloadAutoConvertFormatSubtitle =>
+      'Choose the lossy format used for newly completed downloads.';
+
+  @override
+  String get downloadAutoConvertBitrate => 'Output quality';
+
+  @override
+  String get downloadAutoConvertBitrateSubtitle =>
+      'Higher bitrates preserve more detail but create larger files.';
+
+  @override
+  String get downloadAutoConvertMp3Subtitle =>
+      'Best compatibility across players and devices';
+
+  @override
+  String get downloadAutoConvertM4aSubtitle =>
+      'Efficient AAC audio in an M4A container';
+
+  @override
+  String get downloadAutoConvertOpusSubtitle =>
+      'Best efficiency for modern players';
+
   @override
   String get downloadLossy320Format => 'Lossy 320kbps Format';
 

lib/l10n/app_localizations_es.dart

@@ -1494,6 +1494,39 @@ class AppLocalizationsEs extends AppLocalizations {
   @override
   String get downloadLossyFormat => 'Lossy Format';
 
+  @override
+  String get downloadAutoConvert => 'Auto-convert after download';
+
+  @override
+  String get downloadAutoConvertSubtitle =>
+      'Convert completed downloads to a smaller lossy format. The original is replaced only after conversion succeeds.';
+
+  @override
+  String get downloadAutoConvertFormat => 'Output format';
+
+  @override
+  String get downloadAutoConvertFormatSubtitle =>
+      'Choose the lossy format used for newly completed downloads.';
+
+  @override
+  String get downloadAutoConvertBitrate => 'Output quality';
+
+  @override
+  String get downloadAutoConvertBitrateSubtitle =>
+      'Higher bitrates preserve more detail but create larger files.';
+
+  @override
+  String get downloadAutoConvertMp3Subtitle =>
+      'Best compatibility across players and devices';
+
+  @override
+  String get downloadAutoConvertM4aSubtitle =>
+      'Efficient AAC audio in an M4A container';
+
+  @override
+  String get downloadAutoConvertOpusSubtitle =>
+      'Best efficiency for modern players';
+
   @override
   String get downloadLossy320Format => 'Lossy 320kbps Format';
 

lib/l10n/app_localizations_fr.dart

@@ -1533,6 +1533,39 @@ class AppLocalizationsFr extends AppLocalizations {
   @override
   String get downloadLossyFormat => 'Format avec perte';
 
+  @override
+  String get downloadAutoConvert => 'Auto-convert after download';
+
+  @override
+  String get downloadAutoConvertSubtitle =>
+      'Convert completed downloads to a smaller lossy format. The original is replaced only after conversion succeeds.';
+
+  @override
+  String get downloadAutoConvertFormat => 'Output format';
+
+  @override
+  String get downloadAutoConvertFormatSubtitle =>
+      'Choose the lossy format used for newly completed downloads.';
+
+  @override
+  String get downloadAutoConvertBitrate => 'Output quality';
+
+  @override
+  String get downloadAutoConvertBitrateSubtitle =>
+      'Higher bitrates preserve more detail but create larger files.';
+
+  @override
+  String get downloadAutoConvertMp3Subtitle =>
+      'Best compatibility across players and devices';
+
+  @override
+  String get downloadAutoConvertM4aSubtitle =>
+      'Efficient AAC audio in an M4A container';
+
+  @override
+  String get downloadAutoConvertOpusSubtitle =>
+      'Best efficiency for modern players';
+
   @override
   String get downloadLossy320Format => 'Format avec perte à 320 kbps';
 

lib/l10n/app_localizations_id.dart

@@ -1501,6 +1501,39 @@ class AppLocalizationsId extends AppLocalizations {
   @override
   String get downloadLossyFormat => 'Format Lossy';
 
+  @override
+  String get downloadAutoConvert => 'Konversi otomatis setelah unduh';
+
+  @override
+  String get downloadAutoConvertSubtitle =>
+      'Ubah unduhan yang selesai ke format lossy yang lebih kecil. File asli hanya diganti setelah konversi berhasil.';
+
+  @override
+  String get downloadAutoConvertFormat => 'Format keluaran';
+
+  @override
+  String get downloadAutoConvertFormatSubtitle =>
+      'Pilih format lossy untuk unduhan yang baru selesai.';
+
+  @override
+  String get downloadAutoConvertBitrate => 'Kualitas keluaran';
+
+  @override
+  String get downloadAutoConvertBitrateSubtitle =>
+      'Bitrate lebih tinggi menjaga lebih banyak detail, tetapi ukuran file juga lebih besar.';
+
+  @override
+  String get downloadAutoConvertMp3Subtitle =>
+      'Kompatibilitas terbaik di berbagai pemutar dan perangkat';
+
+  @override
+  String get downloadAutoConvertM4aSubtitle =>
+      'Audio AAC yang efisien dalam container M4A';
+
+  @override
+  String get downloadAutoConvertOpusSubtitle =>
+      'Efisiensi terbaik untuk pemutar modern';
+
   @override
   String get downloadLossy320Format => 'Format Lossy 320kbps';
 

lib/l10n/app_localizations_ja.dart

@@ -1485,6 +1485,39 @@ class AppLocalizationsJa extends AppLocalizations {
   @override
   String get downloadLossyFormat => 'Lossy Format';
 
+  @override
+  String get downloadAutoConvert => 'Auto-convert after download';
+
+  @override
+  String get downloadAutoConvertSubtitle =>
+      'Convert completed downloads to a smaller lossy format. The original is replaced only after conversion succeeds.';
+
+  @override
+  String get downloadAutoConvertFormat => 'Output format';
+
+  @override
+  String get downloadAutoConvertFormatSubtitle =>
+      'Choose the lossy format used for newly completed downloads.';
+
+  @override
+  String get downloadAutoConvertBitrate => 'Output quality';
+
+  @override
+  String get downloadAutoConvertBitrateSubtitle =>
+      'Higher bitrates preserve more detail but create larger files.';
+
+  @override
+  String get downloadAutoConvertMp3Subtitle =>
+      'Best compatibility across players and devices';
+
+  @override
+  String get downloadAutoConvertM4aSubtitle =>
+      'Efficient AAC audio in an M4A container';
+
+  @override
+  String get downloadAutoConvertOpusSubtitle =>
+      'Best efficiency for modern players';
+
   @override
   String get downloadLossy320Format => 'Lossy 320kbps Format';
 

lib/l10n/app_localizations_ko.dart

@@ -1464,6 +1464,39 @@ class AppLocalizationsKo extends AppLocalizations {
   @override
   String get downloadLossyFormat => '손실 압축 형식';
 
+  @override
+  String get downloadAutoConvert => 'Auto-convert after download';
+
+  @override
+  String get downloadAutoConvertSubtitle =>
+      'Convert completed downloads to a smaller lossy format. The original is replaced only after conversion succeeds.';
+
+  @override
+  String get downloadAutoConvertFormat => 'Output format';
+
+  @override
+  String get downloadAutoConvertFormatSubtitle =>
+      'Choose the lossy format used for newly completed downloads.';
+
+  @override
+  String get downloadAutoConvertBitrate => 'Output quality';
+
+  @override
+  String get downloadAutoConvertBitrateSubtitle =>
+      'Higher bitrates preserve more detail but create larger files.';
+
+  @override
+  String get downloadAutoConvertMp3Subtitle =>
+      'Best compatibility across players and devices';
+
+  @override
+  String get downloadAutoConvertM4aSubtitle =>
+      'Efficient AAC audio in an M4A container';
+
+  @override
+  String get downloadAutoConvertOpusSubtitle =>
+      'Best efficiency for modern players';
+
   @override
   String get downloadLossy320Format => '손실 압축 320kbps 형식';
 

lib/l10n/app_localizations_pt.dart

@@ -1494,6 +1494,39 @@ class AppLocalizationsPt extends AppLocalizations {
   @override
   String get downloadLossyFormat => 'Lossy Format';
 
+  @override
+  String get downloadAutoConvert => 'Auto-convert after download';
+
+  @override
+  String get downloadAutoConvertSubtitle =>
+      'Convert completed downloads to a smaller lossy format. The original is replaced only after conversion succeeds.';
+
+  @override
+  String get downloadAutoConvertFormat => 'Output format';
+
+  @override
+  String get downloadAutoConvertFormatSubtitle =>
+      'Choose the lossy format used for newly completed downloads.';
+
+  @override
+  String get downloadAutoConvertBitrate => 'Output quality';
+
+  @override
+  String get downloadAutoConvertBitrateSubtitle =>
+      'Higher bitrates preserve more detail but create larger files.';
+
+  @override
+  String get downloadAutoConvertMp3Subtitle =>
+      'Best compatibility across players and devices';
+
+  @override
+  String get downloadAutoConvertM4aSubtitle =>
+      'Efficient AAC audio in an M4A container';
+
+  @override
+  String get downloadAutoConvertOpusSubtitle =>
+      'Best efficiency for modern players';
+
   @override
   String get downloadLossy320Format => 'Lossy 320kbps Format';
 

lib/l10n/app_localizations_ru.dart

@@ -1505,6 +1505,39 @@ class AppLocalizationsRu extends AppLocalizations {
   @override
   String get downloadLossyFormat => 'Формат с потерями';
 
+  @override
+  String get downloadAutoConvert => 'Auto-convert after download';
+
+  @override
+  String get downloadAutoConvertSubtitle =>
+      'Convert completed downloads to a smaller lossy format. The original is replaced only after conversion succeeds.';
+
+  @override
+  String get downloadAutoConvertFormat => 'Output format';
+
+  @override
+  String get downloadAutoConvertFormatSubtitle =>
+      'Choose the lossy format used for newly completed downloads.';
+
+  @override
+  String get downloadAutoConvertBitrate => 'Output quality';
+
+  @override
+  String get downloadAutoConvertBitrateSubtitle =>
+      'Higher bitrates preserve more detail but create larger files.';
+
+  @override
+  String get downloadAutoConvertMp3Subtitle =>
+      'Best compatibility across players and devices';
+
+  @override
+  String get downloadAutoConvertM4aSubtitle =>
+      'Efficient AAC audio in an M4A container';
+
+  @override
+  String get downloadAutoConvertOpusSubtitle =>
+      'Best efficiency for modern players';
+
   @override
   String get downloadLossy320Format => 'Формат с потерями 320 кбит/с';
 

lib/l10n/app_localizations_tr.dart

@@ -1507,6 +1507,39 @@ class AppLocalizationsTr extends AppLocalizations {
   @override
   String get downloadLossyFormat => 'Kayıplı Format';
 
+  @override
+  String get downloadAutoConvert => 'Auto-convert after download';
+
+  @override
+  String get downloadAutoConvertSubtitle =>
+      'Convert completed downloads to a smaller lossy format. The original is replaced only after conversion succeeds.';
+
+  @override
+  String get downloadAutoConvertFormat => 'Output format';
+
+  @override
+  String get downloadAutoConvertFormatSubtitle =>
+      'Choose the lossy format used for newly completed downloads.';
+
+  @override
+  String get downloadAutoConvertBitrate => 'Output quality';
+
+  @override
+  String get downloadAutoConvertBitrateSubtitle =>
+      'Higher bitrates preserve more detail but create larger files.';
+
+  @override
+  String get downloadAutoConvertMp3Subtitle =>
+      'Best compatibility across players and devices';
+
+  @override
+  String get downloadAutoConvertM4aSubtitle =>
+      'Efficient AAC audio in an M4A container';
+
+  @override
+  String get downloadAutoConvertOpusSubtitle =>
+      'Best efficiency for modern players';
+
   @override
   String get downloadLossy320Format => 'Kayıplı 320kbps Formatı';
 

lib/l10n/app_localizations_uk.dart

@@ -1513,6 +1513,39 @@ class AppLocalizationsUk extends AppLocalizations {
   @override
   String get downloadLossyFormat => 'Формат із втратами';
 
+  @override
+  String get downloadAutoConvert => 'Auto-convert after download';
+
+  @override
+  String get downloadAutoConvertSubtitle =>
+      'Convert completed downloads to a smaller lossy format. The original is replaced only after conversion succeeds.';
+
+  @override
+  String get downloadAutoConvertFormat => 'Output format';
+
+  @override
+  String get downloadAutoConvertFormatSubtitle =>
+      'Choose the lossy format used for newly completed downloads.';
+
+  @override
+  String get downloadAutoConvertBitrate => 'Output quality';
+
+  @override
+  String get downloadAutoConvertBitrateSubtitle =>
+      'Higher bitrates preserve more detail but create larger files.';
+
+  @override
+  String get downloadAutoConvertMp3Subtitle =>
+      'Best compatibility across players and devices';
+
+  @override
+  String get downloadAutoConvertM4aSubtitle =>
+      'Efficient AAC audio in an M4A container';
+
+  @override
+  String get downloadAutoConvertOpusSubtitle =>
+      'Best efficiency for modern players';
+
   @override
   String get downloadLossy320Format => 'Формат із втратами 320 кбіт/с';
 

lib/l10n/arb/app_en.arb

@@ -1991,6 +1991,42 @@
   "@downloadLossyFormat": {
     "description": "Setting title to pick output format for lossy downloads"
   },
+  "downloadAutoConvert": "Auto-convert after download",
+  "@downloadAutoConvert": {
+    "description": "Toggle for automatic post-download audio conversion"
+  },
+  "downloadAutoConvertSubtitle": "Convert completed downloads to a smaller lossy format. The original is replaced only after conversion succeeds.",
+  "@downloadAutoConvertSubtitle": {
+    "description": "Explanation of safe automatic post-download conversion"
+  },
+  "downloadAutoConvertFormat": "Output format",
+  "@downloadAutoConvertFormat": {
+    "description": "Automatic conversion output format setting"
+  },
+  "downloadAutoConvertFormatSubtitle": "Choose the lossy format used for newly completed downloads.",
+  "@downloadAutoConvertFormatSubtitle": {
+    "description": "Automatic conversion format picker explanation"
+  },
+  "downloadAutoConvertBitrate": "Output quality",
+  "@downloadAutoConvertBitrate": {
+    "description": "Automatic conversion bitrate setting"
+  },
+  "downloadAutoConvertBitrateSubtitle": "Higher bitrates preserve more detail but create larger files.",
+  "@downloadAutoConvertBitrateSubtitle": {
+    "description": "Automatic conversion bitrate picker explanation"
+  },
+  "downloadAutoConvertMp3Subtitle": "Best compatibility across players and devices",
+  "@downloadAutoConvertMp3Subtitle": {
+    "description": "MP3 automatic conversion option description"
+  },
+  "downloadAutoConvertM4aSubtitle": "Efficient AAC audio in an M4A container",
+  "@downloadAutoConvertM4aSubtitle": {
+    "description": "M4A AAC automatic conversion option description"
+  },
+  "downloadAutoConvertOpusSubtitle": "Best efficiency for modern players",
+  "@downloadAutoConvertOpusSubtitle": {
+    "description": "Opus automatic conversion option description"
+  },
   "downloadLossy320Format": "Lossy 320kbps Format",
   "@downloadLossy320Format": {
     "description": "Title of the lossy format picker bottom sheet"

lib/l10n/arb/app_id.arb

@@ -4253,6 +4253,42 @@
   "@downloadLossyFormat": {
     "description": "Setting title to pick output format for lossy downloads"
   },
+  "downloadAutoConvert": "Konversi otomatis setelah unduh",
+  "@downloadAutoConvert": {
+    "description": "Toggle for automatic post-download audio conversion"
+  },
+  "downloadAutoConvertSubtitle": "Ubah unduhan yang selesai ke format lossy yang lebih kecil. File asli hanya diganti setelah konversi berhasil.",
+  "@downloadAutoConvertSubtitle": {
+    "description": "Explanation of safe automatic post-download conversion"
+  },
+  "downloadAutoConvertFormat": "Format keluaran",
+  "@downloadAutoConvertFormat": {
+    "description": "Automatic conversion output format setting"
+  },
+  "downloadAutoConvertFormatSubtitle": "Pilih format lossy untuk unduhan yang baru selesai.",
+  "@downloadAutoConvertFormatSubtitle": {
+    "description": "Automatic conversion format picker explanation"
+  },
+  "downloadAutoConvertBitrate": "Kualitas keluaran",
+  "@downloadAutoConvertBitrate": {
+    "description": "Automatic conversion bitrate setting"
+  },
+  "downloadAutoConvertBitrateSubtitle": "Bitrate lebih tinggi menjaga lebih banyak detail, tetapi ukuran file juga lebih besar.",
+  "@downloadAutoConvertBitrateSubtitle": {
+    "description": "Automatic conversion bitrate picker explanation"
+  },
+  "downloadAutoConvertMp3Subtitle": "Kompatibilitas terbaik di berbagai pemutar dan perangkat",
+  "@downloadAutoConvertMp3Subtitle": {
+    "description": "MP3 automatic conversion option description"
+  },
+  "downloadAutoConvertM4aSubtitle": "Audio AAC yang efisien dalam container M4A",
+  "@downloadAutoConvertM4aSubtitle": {
+    "description": "M4A AAC automatic conversion option description"
+  },
+  "downloadAutoConvertOpusSubtitle": "Efisiensi terbaik untuk pemutar modern",
+  "@downloadAutoConvertOpusSubtitle": {
+    "description": "Opus automatic conversion option description"
+  },
   "snackbarAlreadyInLibrary": "\"{trackName}\" sudah ada di perpustakaan Anda",
   "@snackbarAlreadyInLibrary": {
     "description": "Snackbar - track already exists in local library",