feat：优化节点错误处理

app/processor/base.py

@@ -54,6 +54,11 @@ class BaseNode(ABC):
     def process(self, state: T) -> T:
         """子类实现节点核心逻辑，返回状态更新"""
 
+    def fail_on_invalid_output(self, state: T, error: ValueError, reason: str) -> T:
+        """模型输出未通过校验时收尾为失败结果，详细原因只写日志"""
+        self.logger.warning(f"{reason}: {error}")
+        return {**state, "status": "failed", "failure_reason": reason}
+
     def log_step(self, step_name: str, message: str = ""):
         """记录步骤日志。"""
         log_msg = f"[{step_name}]"