feat(app): wire server dedup - force passthrough + PHOTO_DUPLICATE classification & l10n

Task 8: close the gap between server-side duplicate detection (90dcc58)
and the app.

- ApiClient.mapDioException: normalize 409 wire body reusing
  VALIDATION_FAILED with message=PHOTO_DUPLICATE to
  ErrorCodes.photoDuplicate (message-based; auto-compat if the contract
  later adds a dedicated code)
- l10n zh/en errorPhotoDuplicate; error_l10n maps the code (queue page
  inherits via fallback)
- UploadEngine._classifyFailure: PHOTO_DUPLICATE joins the no-auto-retry
  bucket (retrying the same init body would 409 again); force to skip
  dedup travels only through the enqueue path
- UploadTasks drift table +force column (schema v2, addColumn migration;
  legacy rows default false); UploadTaskDraft/UploadTask/prepare carry it
- enqueueForUpload +forcePaths; duplicate dialog "全部上传" (capture page
  + album detail page) now returns DuplicateDialogChoice so confirmed
  duplicates enqueue with force=true (server adjudicates owner/admin)
- engine init body carries force only when true (absent otherwise)

Co-Authored-By: Claude Code <noreply@anthropic.com>

apps/mobile/test/features/uploads/task_store_test.dart

@@ -11,6 +11,8 @@
 /// - datetime 文本落库的亚秒精度。
 library;
 
+import 'package:drift/drift.dart' show driftRuntimeOptions;
+import 'package:drift/native.dart' show NativeDatabase;
 import 'package:flutter_test/flutter_test.dart';
 import 'package:photo_live/features/uploads/task_state.dart';
 import 'package:photo_live/features/uploads/task_store.dart';
@@ -26,6 +28,7 @@ UploadTaskDraft draft({
   String filename = 'IMG_0001.jpg',
   int bytes = 1024,
   String contentType = 'image/jpeg',
+  bool force = false,
 }) {
   return UploadTaskDraft(
     id: id,
@@ -37,6 +40,7 @@ UploadTaskDraft draft({
     filename: filename,
     bytes: bytes,
     contentType: contentType,
+    force: force,
   );
 }
 
@@ -76,6 +80,10 @@ Future<UploadTask> advanceTo(
 }
 
 void main() {
+  // 迁移组在同一测试内另建独立执行器的库（与 setUp 的内存库并存）——
+  // drift 多实例告警在此是误报（见 helpers/fakes.dart 同款处理）。
+  driftRuntimeOptions.dontWarnAboutMultipleDatabases = true;
+
   late TaskStore store;
 
   setUp(() {
@@ -103,6 +111,13 @@ void main() {
       expect(task.bytes, 1024);
       expect(task.createdAt, createdAt);
       expect(task.updatedAt, createdAt);
+      expect(task.force, isFalse, reason: '缺省不强传（服务端查重正常裁决）');
+    });
+
+    test('force=true 落库（弹窗「全部上传」确认强传的任务级标记）', () async {
+      final task = await store.create(draft(force: true));
+      expect(task.force, isTrue);
+      expect((await store.get('alice', 'task-0001'))!.force, isTrue);
     });
 
     test('datetime 文本落库保住亚秒/微秒精度，且本地输入统一 UTC 落库', () async {
@@ -541,4 +556,66 @@ void main() {
       expect(await store.delete('task-0001'), 0, reason: '重复删除返回 0');
     });
   });
+
+  group('schema 迁移（v1 → v2：force 列，Task 8）', () {
+    /// v1 底库（无 force 列）+ 一条既有行，user_version=1——升级后打开。
+    UploadTaskDb legacyV1Db() => UploadTaskDb(
+          NativeDatabase.memory(setup: (raw) {
+            raw.execute('''
+              CREATE TABLE IF NOT EXISTS "upload_tasks" (
+                "id" TEXT NOT NULL PRIMARY KEY,
+                "account_id" TEXT NOT NULL,
+                "album_id" TEXT NOT NULL,
+                "category_id" TEXT NULL,
+                "client_task_id" TEXT NOT NULL,
+                "source_file_path" TEXT NOT NULL,
+                "filename" TEXT NOT NULL,
+                "bytes" INTEGER NOT NULL,
+                "content_type" TEXT NOT NULL,
+                "state" TEXT NOT NULL,
+                "attempt" INTEGER NOT NULL DEFAULT 0,
+                "next_retry_at" TEXT NULL,
+                "server_upload_id" TEXT NULL,
+                "server_photo_id" TEXT NULL,
+                "last_error" TEXT NULL,
+                "cleaned_at" TEXT NULL,
+                "created_at" TEXT NOT NULL,
+                "updated_at" TEXT NOT NULL
+              );
+            ''');
+            raw.execute('''
+              INSERT INTO upload_tasks (
+                "id", "account_id", "album_id", "client_task_id",
+                "source_file_path", "filename", "bytes", "content_type",
+                "state", "created_at", "updated_at"
+              ) VALUES (
+                'task-legacy', 'alice', 'alb-1', 'ct-legacy',
+                '/managed/uploads/alb-1/legacy.jpg', 'IMG_LEGACY.jpg', 2048,
+                'image/jpeg', 'completed',
+                '2026-09-01T00:00:00.000Z', '2026-09-01T00:01:00.000Z'
+              );
+            ''');
+            raw.execute('PRAGMA user_version = 1;');
+          }),
+        );
+
+    test('旧库升级：既有行保留、force=false 默认、新列可写', () async {
+      final db = legacyV1Db();
+      final migrated = TaskStore(db);
+      addTearDown(migrated.close);
+
+      final legacy = await migrated.get('alice', 'task-legacy');
+      expect(legacy, isNotNull, reason: '升级不丢既有行');
+      expect(legacy!.state, UploadTaskState.completed);
+      expect(legacy.filename, 'IMG_LEGACY.jpg');
+      expect(legacy.bytes, 2048);
+      expect(legacy.force, isFalse, reason: 'v1 行无 force 列：迁移默认 false');
+
+      // 升级后新任务可写 force=true（列已由迁移补齐）。
+      final created = await migrated.create(
+        draft(id: 'task-new', clientTaskId: 'ct-new', force: true),
+      );
+      expect(created.force, isTrue);
+    });
+  });
 }