feat：lpmm可选接入memory agent，将memory agent改为标准工具格式，修改llm_utils以兼容

src/chat/knowledge/__init__.py

@@ -30,6 +30,8 @@ DATA_PATH = os.path.join(ROOT_PATH, "data")
 qa_manager = None
 inspire_manager = None
 
+def get_qa_manager():
+    return qa_manager
 
 def lpmm_start_up():  # sourcery skip: extract-duplicate-method
     # 检查LPMM知识库是否启用