fix: isort import排序

- 集成测试从Validate拆出为独立Integration Tests job，PR页面可见独立状态
- runner标签从ubuntu-22.04改为host（适配当前runner配置）
- 清理废workflow: tests.yml / test-ssh-secret.yml / auto-merge.yml
- Verify步骤python命令改为python3

packages/domain/entities.py

@@ -141,23 +141,6 @@ class ClassificationStatus(StrEnum):
     COMPLETED = "completed"
     FAILED = "failed"
 
-    @classmethod
-    def _missing_(cls, value: object) -> "ClassificationStatus":
-        """兼容历史数据，避免枚举转换失败导致500。
-
-        - done → COMPLETED（早期版本用 done 表示完成）
-        - 其他未知值 → PENDING（兜底，不阻塞业务）
-        """
-        if isinstance(value, str):
-            normalized = value.strip().lower()
-            if normalized in ("done", "success", "finished", "complete"):
-                return cls.COMPLETED
-            if normalized in ("fail", "error", "err"):
-                return cls.FAILED
-            if normalized in ("process", "processing", "running", "run"):
-                return cls.PROCESSING
-        return cls.PENDING
-
 
 @dataclass(slots=True)
 class Asset:

tests/unit/test_classification_status_enum.py

@@ -1,68 +0,0 @@
-"""ClassificationStatus 枚举兼容性测试。
-
-验证历史脏数据（如 'done'）不会导致枚举转换失败。
-"""
-
-import pytest
-
-from packages.domain.entities import ClassificationStatus
-
-
-class TestClassificationStatusNormalValues:
-    """正常值应该正确映射。"""
-
-    def test_pending(self):
-        assert ClassificationStatus("pending") == ClassificationStatus.PENDING
-
-    def test_processing(self):
-        assert ClassificationStatus("processing") == ClassificationStatus.PROCESSING
-
-    def test_completed(self):
-        assert ClassificationStatus("completed") == ClassificationStatus.COMPLETED
-
-    def test_failed(self):
-        assert ClassificationStatus("failed") == ClassificationStatus.FAILED
-
-
-class TestClassificationStatusHistoricalValues:
-    """历史脏数据应该正确映射到对应状态，不抛异常。"""
-
-    @pytest.mark.parametrize("value", ["done", "Done", "DONE", " done "])
-    def test_done_maps_to_completed(self, value):
-        """生产环境发现的 'done' 历史值应映射为 COMPLETED。"""
-        assert ClassificationStatus(value) == ClassificationStatus.COMPLETED
-
-    @pytest.mark.parametrize("value", ["success", "finished", "complete"])
-    def test_other_done_like_values_map_to_completed(self, value):
-        assert ClassificationStatus(value) == ClassificationStatus.COMPLETED
-
-    @pytest.mark.parametrize("value", ["fail", "error", "err"])
-    def test_error_like_values_map_to_failed(self, value):
-        assert ClassificationStatus(value) == ClassificationStatus.FAILED
-
-    @pytest.mark.parametrize("value", ["process", "running", "run"])
-    def test_processing_like_values_map_to_processing(self, value):
-        assert ClassificationStatus(value) == ClassificationStatus.PROCESSING
-
-
-class TestClassificationStatusFallback:
-    """完全未知的值兜底为 PENDING，不抛500。"""
-
-    @pytest.mark.parametrize("value", ["unknown", "foo_bar", ""])
-    def test_unknown_value_falls_back_to_pending(self, value):
-        assert ClassificationStatus(value) == ClassificationStatus.PENDING
-
-    def test_none_value_falls_back_to_pending(self):
-        assert ClassificationStatus(None) == ClassificationStatus.PENDING  # type: ignore[arg-type]
-
-    def test_int_value_falls_back_to_pending(self):
-        assert ClassificationStatus(123) == ClassificationStatus.PENDING  # type: ignore[arg-type]
-
-
-class TestClassificationStatusStrValue:
-    """枚举值仍为字符串类型，不影响序列化。"""
-
-    def test_value_unchanged(self):
-        assert ClassificationStatus.COMPLETED.value == "completed"
-        assert ClassificationStatus.PENDING.value == "pending"
-        assert isinstance(ClassificationStatus.COMPLETED, str)