feat(agent): 增强多模态链路与工具调用能力

backend/tests/unit/v1/agent/test_router_guards.py

@@ -175,3 +175,53 @@ async def test_enqueue_resume_accepts_valid_tool_contract(
     assert result.task_id == "task-resume-1"
     assert result.thread_id == "00000000-0000-0000-0000-000000000001"
     assert result.run_id == "run-resume-1"
+
+
+@pytest.mark.asyncio
+async def test_stream_events_retries_on_redis_timeout(
+    monkeypatch: pytest.MonkeyPatch,
+) -> None:
+    async def _acquire(*, user_id: str) -> bool:
+        del user_id
+        return True
+
+    async def _release(*, user_id: str) -> None:
+        del user_id
+
+    monkeypatch.setattr(agent_router, "_acquire_sse_slot", _acquire)
+    monkeypatch.setattr(agent_router, "_release_sse_slot", _release)
+
+    class _Request:
+        async def is_disconnected(self) -> bool:
+            return False
+
+    class _Service:
+        def __init__(self) -> None:
+            self.calls = 0
+
+        async def stream_events(self, **kwargs):  # noqa: ANN003
+            del kwargs
+            self.calls += 1
+            if self.calls == 1:
+                raise RuntimeError("Timeout reading from localhost:6379")
+            if self.calls == 2:
+                return [{"id": "1-0", "event": {"type": "RUN_FINISHED"}}]
+            return []
+
+    response = await agent_router.stream_events(
+        request=cast(Any, _Request()),
+        thread_id="00000000-0000-0000-0000-000000000001",
+        service=cast(Any, _Service()),
+        current_user=CurrentUser(id=uuid4(), email="user@example.com"),
+        last_event_id=None,
+        idle_limit=2,
+    )
+
+    chunks: list[str] = []
+    async for chunk in response.body_iterator:
+        chunks.append(str(chunk))
+        if any("RUN_FINISHED" in item for item in chunks):
+            break
+
+    merged = "".join(chunks)
+    assert "event: RUN_FINISHED" in merged