fix(tasks): isolate peripheral feedback writes by execution scope

An old development synchronizer could overwrite a production recovery timestamp in a shared project database even after production deployment. Check task scope before feedback or source-withdrawal writes and before idempotency replay.

Cover cross-scope rejection, same-scope success and replay, and preserve actual field feedback time when later order metadata changes.

tests/unit/test_operational_tasks.py

@@ -2487,3 +2487,59 @@ def test_task_scope_is_required_in_persisted_contract():
         OperationalTaskSummary.model_validate(task)
     assert any(item["loc"] == ("execution_scope",) and item["type"] == "missing"
                for item in error.value.errors())
+
+
+@pytest.mark.anyio
+@pytest.mark.parametrize("operation", ["feedback", "withdrawal"])
+@pytest.mark.parametrize("task_scope,server_scope,allowed", [
+    (None, "production", False),
+    (None, "development", False),
+    ("production", "production", True),
+    ("production", "development", False),
+    ("development", "production", False),
+    ("development", "development", True),
+])
+async def test_external_sync_only_mutates_tasks_in_its_execution_scope(operation, task_scope, server_scope, allowed):
+    from copy import deepcopy
+
+    now = datetime(2026, 11, 8, tzinfo=timezone.utc)
+    context = _context()
+    task = _task_document(context, now, lease=None)
+    source_id = f"peripheral_sample:{uuid4()}"
+    task.update(task_type="external_work_order", source={
+        "kind": "external_system", "external_id": source_id,
+        "external_revision": 1, "event_kind": "general",
+    })
+    if task_scope is None:
+        task.pop("execution_scope")
+    else:
+        task["execution_scope"] = task_scope
+    repository = TaskRepository(task)
+    service = OperationalTaskService(repository, context, set(), clock=lambda: now, execution_scope=server_scope)
+    if operation == "feedback":
+        command = ExternalFeedbackCommand(request_id=uuid4(), source_event_id=source_id,
+            source_revision=2, status="completed", occurred_at=now, detail="已关阀修复管道")
+        method = "external_feedback"
+    else:
+        command = ExternalSourceWithdrawalCommand(request_id=uuid4(), source_event_id=source_id)
+        method = "withdraw_external_source"
+    before = deepcopy(repository.task)
+    if not allowed:
+        with pytest.raises(DomainError) as error:
+            await getattr(service, method)(task["task_id"], command)
+        assert error.value.code == "EXECUTION_SCOPE_MISMATCH" and error.value.status == 403
+        assert repository.task == before
+        assert repository.feedback == repository.evidence == repository.requests == {}
+        return
+
+    await getattr(service, method)(task["task_id"], command)
+    assert repository.task["status"] == ("completed" if operation == "feedback" else "cancelled")
+    # Check scope before idempotency replay as well as before the first write.
+    await getattr(service, method)(task["task_id"], command)
+    before = deepcopy(repository.task)
+    other = OperationalTaskService(repository, context, set(), clock=lambda: now,
+        execution_scope="development" if server_scope == "production" else "production")
+    with pytest.raises(DomainError) as error:
+        await getattr(other, method)(task["task_id"], command)
+    assert error.value.code == "EXECUTION_SCOPE_MISMATCH" and error.value.status == 403
+    assert repository.task == before