fix: on_waiting_llm_request hook did not check message validity (#4349)

* fix:修复waitingllmrequest没有检查消息有效性的问题

* 进行ruff修复

astrbot/core/pipeline/process_stage/method/agent_sub_stages/internal.py

@@ -361,6 +361,14 @@ class InternalAgentSubStage(Stage):
             if (enable_streaming := event.get_extra("enable_streaming")) is not None:
                 streaming_response = bool(enable_streaming)
 
+            # 检查消息内容是否有效，避免空消息触发钩子
+            has_provider_request = event.get_extra("provider_request") is not None
+            has_valid_message = bool(event.message_str and event.message_str.strip())
+
+            if not has_provider_request and not has_valid_message:
+                logger.debug("skip llm request: empty message and no provider_request")
+                return
+
             logger.debug("ready to request llm provider")
 
             # 通知等待调用 LLM（在获取锁之前）