feat(client): 对接详情/播放/进度续看/收藏（K1 看剧闭环）+ 三态 UI

后端接口从 6 个扩到 13 个，全部走真数据：

- 新增 api：playback_api（/app/episodes/{id}/play）、watch_api（/app/watch/*）、
  library_api（/app/favorites*）；票据从 CatalogApi 搬到 PlaybackApi
- 新增 repository：PlaybackRepository（含票据 TTL 缓存，默认 10 分钟，时钟可注入）、
  FavoriteRepository、WatchHistoryRepository 换成服务端模型（每剧一条续看记录，删掉 demoProfileId）
- PlayerLogic：起播前取票（拿不到给三态 UI，失败可重试）；accessType 驱动锁定文案，
  不在前端猜；签名地址原样交给播放器（只补 host，不动 path/query）；
  进度上报节流 5s → 10s，切集/退出/切后台各补一次，播完带 finished
- 续看定位：服务端记录里的那一集才 seek（其它集从头播），续看位置进详情/播放页时读一次
- FavoriteController：收藏以服务端为准，乐观更新 + 失败回滚；退出登录清空
- UI 三态：详情页（加载/失败可重试/空剧集 + 续看进度条 + 收藏按钮）、
  播放页（票据加载中/失败可重试/后端判定不可播）、我的页（续看失败可重试、收藏三态、最近观看）
- l10n 新增 8 个键（en/zh/id 三份）：网络/进度/收藏失败、锁定提示、续看文案等

测试：flutter test 188 全过（存量 27 个测试文件未跑红）；新增票据过期重取、进度节流、
续看定位、收藏回滚、签名 query 原样保留、真实后端端到端联调（live_watch_flow）

lib/core/data/models/play_ticket.dart

@@ -1,12 +1,18 @@
+import 'json_numbers.dart';
+
 /// 播放票据：客户端据此决定直接播放、提示解锁还是提示暂无片源。
 class PlayTicket {
   const PlayTicket({
     required this.episodeId,
     required this.accessible,
     required this.accessType,
+    this.dramaId = '',
+    this.number = 0,
+    this.title = '',
     this.playUrl = '',
     this.durationSec = 0,
     this.unlockCoin = 0,
+    this.previewSeconds = 0,
   });
 
   static const String free = 'FREE';
@@ -15,23 +21,35 @@ class PlayTicket {
   static const String noMedia = 'NO_MEDIA';
 
   final String episodeId;
+  final String dramaId;
+  final int number;
+  final String title;
   final bool accessible;
   final String accessType;
+
+  /// 签名播放地址：**原样使用**（含 `?e=&s=`），客户端不拼接、不改写。
   final String playUrl;
   final int durationSec;
   final int unlockCoin;
 
+  /// 试看秒数：仅 `COIN_REQUIRED` 时有意义（付费解锁在 B2 做）。
+  final int previewSeconds;
+
   bool get needsUnlock =>
       accessType == coinRequired || accessType == vipRequired;
 
   factory PlayTicket.fromJson(Map<String, dynamic> json) {
     return PlayTicket(
       episodeId: (json['episodeId'] ?? '').toString(),
+      dramaId: (json['dramaId'] ?? '').toString(),
+      number: jsonToInt(json['number']),
+      title: json['title'] as String? ?? '',
       accessible: json['accessible'] == true,
       accessType: json['accessType'] as String? ?? noMedia,
       playUrl: json['playUrl'] as String? ?? '',
-      durationSec: (json['durationSec'] as num?)?.toInt() ?? 0,
-      unlockCoin: (json['unlockCoin'] as num?)?.toInt() ?? 0,
+      durationSec: jsonToInt(json['durationSec']),
+      unlockCoin: jsonToInt(json['unlockCoin']),
+      previewSeconds: jsonToInt(json['previewSeconds']),
     );
   }
 }

lib/core/data/models/watch_progress.dart

@@ -0,0 +1,61 @@
+// Author: fruit.com.cn
+
+import 'json_numbers.dart';
+
+/// 服务端续看记录：`GET /app/watch/progress?dramaId=` 与 `/app/watch/recent` 的下发结构。
+///
+/// 服务端按 `(user, drama)` 只留一条，所以它是"这部剧看到哪一集的哪一秒"，
+/// 不是逐集进度。ID 与毫秒都是字符串（见 api-phase1.md §0），统一走 jsonToInt 解析。
+class WatchProgress {
+  const WatchProgress({
+    required this.dramaId,
+    required this.episodeId,
+    required this.position,
+    required this.duration,
+    this.finished = false,
+    this.playCount = 0,
+  });
+
+  final String dramaId;
+  final String episodeId;
+  final Duration position;
+  final Duration duration;
+  final bool finished;
+  final int playCount;
+
+  bool get hasPosition => position > Duration.zero;
+
+  /// 进度比例 0~1，时长未知时为 0，避免 UI 出现 NaN。
+  double get fraction {
+    if (duration <= Duration.zero) return 0;
+    return (position.inMilliseconds / duration.inMilliseconds).clamp(0.0, 1.0);
+  }
+
+  factory WatchProgress.fromJson(Map<String, dynamic> json) {
+    return WatchProgress(
+      dramaId: (json['dramaId'] ?? '').toString(),
+      episodeId: (json['episodeId'] ?? '').toString(),
+      position: Duration(milliseconds: jsonToInt(json['positionMs'])),
+      duration: Duration(milliseconds: jsonToInt(json['durationMs'])),
+      finished: json['finished'] == true,
+      playCount: jsonToInt(json['playCount']),
+    );
+  }
+
+  Map<String, dynamic> toJson() => {
+    'dramaId': dramaId,
+    'episodeId': episodeId,
+    'positionMs': position.inMilliseconds,
+    'durationMs': duration.inMilliseconds,
+    'finished': finished,
+    'playCount': playCount,
+  };
+}
+
+/// 续看点：从哪一集的哪个位置继续看。
+class ResumePoint {
+  const ResumePoint({required this.episodeId, required this.position});
+
+  final String episodeId;
+  final Duration position;
+}