fix(ai-outfit): 停止生成打断当前目录行 + 「停止中…」反馈 (§19.24)

修「开始生成→几秒后停止→两个按钮都灰几十秒像卡死」：非死锁，是温和停止
在等当前目录行收尾，而 _generate_directory_outfit 一次性 submit 全部图片、
shutdown(wait=True) 等全跑完，停止信号进不到该循环；且 _stop 后无反馈。

- outfit_batch：run() 经 _accepts_should_stop 给 generate_func 传 should_stop
  (= _stop_event.is_set)，2-arg 才传、1-arg 仍兼容（含既有 mock）
- ai_outfit：generate_outfit_image/_generate_directory_outfit 增 should_stop；
  目录循环改有界提交——始终最多 image_concurrency 张在飞，每张完成后、提交
  下一张前查 should_stop，已停止则停止提交、在飞收尾即返回（结果注明
  「已停止，N 张未生成」，已生成的带 output_paths）
- 面板：_OutfitWorker.gen(task, should_stop) 透传；_stop() 把停止按钮改
  「停止中…」；_set_running(False) 复位「停止生成」

测试：目录行 should_stop 触发后只生成到停止点、返回「已停止」结果；2-arg
generate_func 收到 should_stop；既有用例（1-arg mock、目录并发/部分失败）保持绿。
全套 py37 通过（test_config_service 的 packaging 模板失败属并行 §19.13，无关）。
离屏冒烟：stop 截断 run 且 runner 及时返回；面板停止按钮「停止中…」→结束复位。

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

tests/test_ai_outfit.py

@@ -264,6 +264,28 @@ class TestAiOutfitCore(unittest.TestCase):
         self.assertEqual(len(result.output_paths), 2)
         self.assertFalse((out / "a" / "img2.jpg").exists())
 
+    def test_generate_directory_stops_remaining_on_should_stop(self):
+        """§19.24: should_stop 触发后不再提交剩余图片，返回「已停止」结果。"""
+        from core.ai_outfit import generate_outfit_image
+
+        d = self._make_dir_with_images("a")     # 3 images, image_concurrency=1
+        out = self.tmp / "out"
+        client = _RecordingClient(self._image_bytes())
+
+        # stop as soon as the first image has been generated
+        def should_stop():
+            return client.calls >= 1
+
+        result = generate_outfit_image(
+            self._dir_task(d), "话术", out, model_config={},
+            api_client=client, should_stop=should_stop)
+
+        self.assertFalse(result.success)
+        self.assertEqual(client.calls, 1)        # only 1 generated; rest not submitted
+        self.assertIn("已停止", result.error)
+        self.assertIn("2 张未生成", result.error)
+        self.assertEqual(len(result.output_paths), 1)
+
     def test_generate_directory_uses_image_concurrency(self):
         from core.ai_outfit import generate_outfit_image
 

tests/test_outfit_batch.py

@@ -67,6 +67,23 @@ class TestOutfitBatchRunner(unittest.TestCase):
         self.assertEqual(summary.failure_count, 0)
         self.assertEqual(progress, [(1, 2, 2), (2, 2, 3)])
 
+    def test_two_arg_generate_func_receives_should_stop(self):
+        """§19.24: 2-arg generate_func 收到 should_stop callable；1-arg 仍兼容。"""
+        from core.outfit_batch import OutfitBatchOptions, OutfitBatchRunner
+
+        seen = []
+
+        def generate(task, should_stop):
+            seen.append(callable(should_stop) and should_stop() is False)
+            return _result(task, True)
+
+        OutfitBatchRunner(
+            [_task(2), _task(3)], generate_func=generate,
+            options=OutfitBatchOptions(concurrency=1),
+        ).run()
+
+        self.assertEqual(seen, [True, True])   # both rows got a working should_stop
+
     def test_retry_until_success(self):
         from core.outfit_batch import OutfitBatchOptions, OutfitBatchRunner