feat(app): 完成 P0 钱包解锁、下载落盘与手机号登录

lib/pages/downloads/downloads_page.dart

@@ -7,6 +7,7 @@ import 'package:provider/provider.dart';
 
 import '../../core/data/models/download_license.dart';
 import '../../core/data/models/download_policy.dart';
+import '../../core/data/models/drama.dart';
 import '../../core/data/services/auth_controller.dart';
 import '../../core/data/services/download_controller.dart';
 import '../../core/formatting/error_text.dart';
@@ -18,6 +19,7 @@ import '../../core/theme/app_theme.dart';
 import '../../core/widgets/auth_gate.dart';
 import '../../core/widgets/empty_state.dart';
 import '../../l10n/app_localizations.dart';
+import '../player/player_view.dart';
 import 'downloads_binding.dart';
 
 /// 下载授权与状态管理页；本批不落盘，只管理服务端授权。
@@ -135,7 +137,12 @@ class _DownloadsBody extends StatelessWidget {
             for (final license in downloads.licenses) ...[
               _LicenseTile(
                 license: license,
+                downloads: downloads,
                 onRemove: () => _remove(context, license.episodeId),
+                onPlay: () => _playOffline(context, license),
+                onDownload: () => unawaited(
+                  downloads.startDownload(license.episodeId, license: license),
+                ),
               ),
               const SizedBox(height: 10),
             ],
@@ -144,6 +151,32 @@ class _DownloadsBody extends StatelessWidget {
     );
   }
 
+  void _playOffline(BuildContext context, DownloadLicense license) {
+    final drama = Drama(
+      id: license.dramaId,
+      title: license.dramaTitle,
+      synopsis: '',
+      posterUrl: '',
+      episodes: [
+        Episode(
+          id: license.episodeId,
+          number: license.episodeNo,
+          title: 'Episode ${license.episodeNo}',
+          isFree: true,
+        ),
+      ],
+    );
+    Navigator.of(context).push(
+      MaterialPageRoute<void>(
+        builder: (_) => PlayerPage(
+          drama: drama,
+          initialIndex: 0,
+          downloads: downloads,
+        ),
+      ),
+    );
+  }
+
   Future<void> _remove(BuildContext context, String episodeId) async {
     unawaited(context.read<Haptics>().mediumImpact());
     final ok = await downloads.remove(episodeId);
@@ -302,14 +335,35 @@ class _PolicyPanel extends StatelessWidget {
 }
 
 class _LicenseTile extends StatelessWidget {
-  const _LicenseTile({required this.license, required this.onRemove});
+  const _LicenseTile({
+    required this.license,
+    required this.downloads,
+    required this.onRemove,
+    required this.onPlay,
+    required this.onDownload,
+  });
 
   final DownloadLicense license;
+  final DownloadController downloads;
   final VoidCallback onRemove;
+  final VoidCallback onPlay;
+  final VoidCallback onDownload;
 
   @override
   Widget build(BuildContext context) {
     final l10n = AppLocalizations.of(context)!;
+    final downloaded = downloads.isDownloaded(license.episodeId);
+    final downloading = downloads.isDownloading(license.episodeId);
+    final progress = downloaded
+        ? 1.0
+        : downloading
+        ? downloads.progressFor(license.episodeId)
+        : license.progressPercent / 100;
+    final taskStatus = downloaded
+        ? 'COMPLETED'
+        : downloading
+        ? 'DOWNLOADING'
+        : license.taskStatus;
     return Container(
       key: ValueKey('download-license-${license.episodeId}'),
       padding: const EdgeInsets.all(12),
@@ -335,6 +389,20 @@ class _LicenseTile extends StatelessWidget {
                 ),
               ),
               Text(l10n.episodeLabel(license.episodeNo)),
+              if (downloaded)
+                IconButton(
+                  key: ValueKey('download-play-${license.episodeId}'),
+                  tooltip: l10n.play,
+                  onPressed: onPlay,
+                  icon: const Icon(Icons.play_circle_outline_rounded),
+                )
+              else if (!downloading)
+                IconButton(
+                  key: ValueKey('download-start-${license.episodeId}'),
+                  tooltip: l10n.downloads,
+                  onPressed: onDownload,
+                  icon: const Icon(Icons.download_rounded),
+                ),
               IconButton(
                 key: ValueKey('download-remove-${license.episodeId}'),
                 tooltip: l10n.remove,
@@ -352,7 +420,7 @@ class _LicenseTile extends StatelessWidget {
                 style: const TextStyle(color: AppColors.blueSoft, fontSize: 12),
               ),
               Text(
-                l10n.downloadTaskStatus(license.taskStatus),
+                l10n.downloadTaskStatus(taskStatus),
                 style: const TextStyle(color: AppColors.muted, fontSize: 12),
               ),
               Text(
@@ -371,7 +439,7 @@ class _LicenseTile extends StatelessWidget {
             borderRadius: BorderRadius.circular(AppDimens.progressRadius),
             child: LinearProgressIndicator(
               minHeight: AppDimens.progressHeight,
-              value: (license.progressPercent / 100).clamp(0.0, 1.0),
+              value: progress.clamp(0.0, 1.0),
               backgroundColor: Colors.white24,
               valueColor: const AlwaysStoppedAnimation(AppColors.blueSoft),
             ),