fix: preserve task stop intent and guard remote execution boundaries

backend/tests/test_opencode_tasks.py

@@ -5,6 +5,16 @@ from services.background_tasks.opencode import OpenCodeExecutor
 
 
 class OpenCodeTaskTest(unittest.IsolatedAsyncioTestCase):
+    async def test_persisted_result_keeps_long_assistant_text(self):
+        text = "重要前提：仅完成部分修改。" + "结果" * 10000 + "仍有失败。"
+        async def respond(request):
+            if request.url.path.endswith("/message"):
+                return httpx.Response(200, json=[{"info": {"role": "assistant", "parentID": "msg_test", "time": {"completed": 1}}, "parts": [{"type": "text", "text": text}]}])
+            return httpx.Response(200, json={})
+        executor = OpenCodeExecutor({"url": "https://remote.test", "directory": "/demo"}, {}, transport=httpx.MockTransport(respond))
+        state = await executor.snapshot({"session_id": "ses_test", "message_id": "msg_test"})
+        self.assertEqual(state["result"], text)
+
     async def test_correlated_completion_ignores_initial_idle_and_other_sessions(self):
         handle = {"session_id": "ses_test", "message_id": "msg_test"}
         submitted = False