Update default_generator.py

src/chat/replyer/default_generator.py

@@ -956,6 +956,11 @@ async def get_prompt_info(message: str, threshold: float):
     logger.debug(f"获取知识库内容，元消息：{message[:30]}...，消息长度: {len(message)}")
     # 从LPMM知识库获取知识
     try:
+        # 检查LPMM知识库是否启用
+        if qa_manager is None:
+            logger.debug("LPMM知识库已禁用，跳过知识获取")
+            return ""
+            
         found_knowledge_from_lpmm = qa_manager.get_knowledge(message)
 
         end_time = time.time()