feat: upgrade Flutter version to 3.38 (#1256)

ui/flutter/lib/api/model/downloader_config.dart

@@ -12,13 +12,12 @@ class DownloaderConfig {
   WebhookConfig webhook = WebhookConfig();
   AutoTorrentConfig autoTorrent = AutoTorrentConfig();
   ArchiveConfig archive = ArchiveConfig();
-
-  // New fields for auto-management
-  bool autoDeleteMissingFileTasks = false;
+  bool autoDeleteMissingFileTasks;
 
   DownloaderConfig({
     this.downloadDir = '',
     this.maxRunning = 0,
+    this.autoDeleteMissingFileTasks = false,
   });
 
   factory DownloaderConfig.fromJson(Map<String, dynamic> json) =>

ui/flutter/lib/api/model/downloader_config.g.dart

@@ -10,6 +10,8 @@ DownloaderConfig _$DownloaderConfigFromJson(Map<String, dynamic> json) =>
     DownloaderConfig(
       downloadDir: json['downloadDir'] as String? ?? '',
       maxRunning: (json['maxRunning'] as num?)?.toInt() ?? 0,
+      autoDeleteMissingFileTasks:
+          json['autoDeleteMissingFileTasks'] as bool? ?? false,
     )
       ..protocolConfig = ProtocolConfig.fromJson(
           json['protocolConfig'] as Map<String, dynamic>?)
@@ -20,8 +22,7 @@ DownloaderConfig _$DownloaderConfigFromJson(Map<String, dynamic> json) =>
       ..autoTorrent = AutoTorrentConfig.fromJson(
           json['autoTorrent'] as Map<String, dynamic>?)
       ..archive =
-          ArchiveConfig.fromJson(json['archive'] as Map<String, dynamic>?)
-      ..autoDeleteMissingFileTasks = json['autoDeleteMissingFileTasks'] as bool;
+          ArchiveConfig.fromJson(json['archive'] as Map<String, dynamic>?);
 
 Map<String, dynamic> _$DownloaderConfigToJson(DownloaderConfig instance) =>
     <String, dynamic>{