docs: support multi-project delivery units (#13)

tests/test_harness_docs.py

@@ -97,6 +97,24 @@ class TaskTemplateTests(unittest.TestCase):
             errors,
         )
 
+    def test_task_template_requires_subproject_impact(self) -> None:
+        with tempfile.TemporaryDirectory() as directory:
+            root = Path(directory)
+            template = root / ".gitea" / "issue_template" / "task.md"
+            template.parent.mkdir(parents=True)
+            template.write_text("## 基本信息\n", encoding="utf-8")
+            errors: list[str] = []
+            check_task_template(errors, root)
+        self.assertIn("单元任务模板缺少：## 子项目影响", errors)
+        self.assertIn(
+            "单元任务模板缺少：- 是否跨子项目：是 / 否",
+            errors,
+        )
+        self.assertIn(
+            "单元任务模板缺少：- 是否修改共享接口或契约：是 / 否；唯一事实来源：",
+            errors,
+        )
+
     def test_task_template_requires_dependency_fields(self) -> None:
         with tempfile.TemporaryDirectory() as directory:
             root = Path(directory)