Close lifecycle transition helper workplan

tests/test_routers_core.py

@@ -597,6 +597,58 @@ class TestReconciliationEndpoints:
         r = await client.get(f"/tasks/{task['id']}")
         assert r.json()["status"] == "in_progress"
 
+    async def test_apply_task_start_write_through_activates_parent_file_and_db(self, client, tmp_path):
+        await _create_domain(client)
+        repo_root = tmp_path / "repo"
+        workplans = repo_root / "workplans"
+        workplans.mkdir(parents=True)
+        repo = await _create_repo(client, local_path=repo_root)
+        topic = await _create_topic(client)
+        ws = await _create_workstream(client, topic["id"], repo_id=repo["id"], status="ready")
+        task = await _create_task(client, ws["id"])
+        wp = workplans / "STATE-WP-9999-demo.md"
+        wp.write_text(
+            "---\n"
+            "id: STATE-WP-9999\n"
+            "type: workplan\n"
+            "title: Demo\n"
+            "domain: custodian\n"
+            "repo: state-hub\n"
+            "status: ready\n"
+            f"state_hub_workstream_id: \"{ws['id']}\"\n"
+            "---\n\n"
+            "## Demo Task\n\n"
+            "```task\n"
+            "id: STATE-WP-9999-T01\n"
+            "status: todo\n"
+            "priority: high\n"
+            f"state_hub_task_id: \"{task['id']}\"\n"
+            "```\n",
+            encoding="utf-8",
+        )
+
+        r = await client.post("/reconciliation/state-change", json={
+            "target_type": "task",
+            "target_id": task["id"],
+            "target_status": "in_progress",
+            "actor": "dashboard",
+            "expected_current_status": "todo",
+            "apply": True,
+        })
+
+        assert r.status_code == 200, r.text
+        body = r.json()
+        assert body["write_through_result"] == "applied"
+        text = wp.read_text(encoding="utf-8")
+        assert "status: active" in text
+        assert "status: in_progress" in text
+
+        r = await client.get(f"/workstreams/{ws['id']}")
+        assert r.json()["status"] == "active"
+
+        r = await client.get(f"/tasks/{task['id']}")
+        assert r.json()["status"] == "in_progress"
+
     async def test_apply_task_confirmation_case_creates_reconciliation_message(self, client, tmp_path):
         await _create_domain(client)
         repo_root = tmp_path / "repo"