feat: save pipeline config snapshot in async task execution

Author: dcy

backend/app/services/task_registry.py

@@ -439,6 +439,8 @@ async def start_execution_async(
         # 创建初始结果
         initial_result = {
             "task_id": task_id,
+            "pipeline_id": pipeline_id,
+            "pipeline_config": pipeline_config,
             "status": "queued",
             "output": {},
             "logs": [f"[{self.get_current_time()}] Pipeline execution queued"],