fix: stream large graph JSON imports

tests/test_project_lifecycle.py

@@ -172,6 +172,13 @@ class ProjectPayloadValidationTests(unittest.TestCase):
 
         self.assertIn("数据与所选区域 贵阳市 不一致", "；".join(raised.exception.errors))
 
+    def test_map_poi_flag_must_be_boolean_not_a_string(self) -> None:
+        body = valid_payload()
+        body["graph_data"]["nodes"][0]["properties"]["map_poi"] = "false"
+        with self.assertRaises(ProjectValidationError) as raised:
+            normalize_provision_payload(body)
+        self.assertIn("map_poi 必须是布尔值", "；".join(raised.exception.errors))
+
     def test_spatial_map_accepts_legacy_city_name_when_adcode_is_missing(self) -> None:
         body = valid_payload()
         body["schema"]["entity_types"]["Place"]["fields"].update({