Refactor session runtime persistence

tests/test_gui_server.py

@@ -483,6 +483,21 @@ class GuiServerTests(unittest.TestCase):
                 },
                 {'role': 'user', 'content': 'continue'},
             ),
+            display_messages=(
+                {'role': 'user', 'content': 'hello'},
+                {
+                    'role': 'assistant',
+                    'content': '上一次任务已中断，后台没有正在执行的进程。',
+                    'state': 'final',
+                    'stop_reason': 'interrupted',
+                    'metadata': {'kind': 'run_status', 'status': 'interrupted'},
+                },
+                {
+                    'role': 'user',
+                    'content': 'pending',
+                    'metadata': {'status': 'running', 'placeholder': True},
+                },
+            ),
             turns=1,
             tool_calls=0,
             usage={},
@@ -498,6 +513,10 @@ class GuiServerTests(unittest.TestCase):
             [message['content'] for message in sanitized.messages],
             ['hello', 'continue'],
         )
+        self.assertEqual(
+            [message['content'] for message in sanitized.display_messages],
+            ['hello'],
+        )
 
     def test_runtime_event_stage_names_long_running_work(self) -> None:
         self.assertEqual(