Update pfc_KnowledgeFetcher.py

src/experimental/PFC/pfc_KnowledgeFetcher.py

@@ -35,6 +35,11 @@ class KnowledgeFetcher:
 
         logger.debug(f"[私聊][{self.private_name}]正在从LPMM知识库中获取知识")
         try:
+            # 检查LPMM知识库是否启用
+            if qa_manager is None:
+                logger.debug(f"[私聊][{self.private_name}]LPMM知识库已禁用，跳过知识获取")
+                return "未找到匹配的知识"
+                
             knowledge_info = qa_manager.get_knowledge(query)
             logger.debug(f"[私聊][{self.private_name}]LPMM知识库查询结果: {knowledge_info:150}")
             return knowledge_info