fix: 修复在线时间记录的db_save调用

- db_save需要key_field和key_value参数用于get_or_create
- 创建新记录应使用db_query with query_type='create'
- 修复'db_save() missing 2 required positional arguments'错误

src/chat/utils/statistic.py

@@ -102,8 +102,9 @@ class OnlineTimeRecordTask(AsyncTask):
                     )
                 else:
                     # 创建新记录
-                    new_record = await db_save(
+                    new_record = await db_query(
                         model_class=OnlineTime,
+                        query_type="create",
                         data={
                             "timestamp": str(current_time),
                             "duration": 5,  # 初始时长为5分钟