fix cancel order

src/trade_server.py

@@ -542,6 +542,12 @@ def cancel(entrust_no):
         result = get_trader().cancel(entrust_no)
         logger.info(f"Cancel result: {result}")
 
+        # 如果取消成功，从pending_orders中移除该订单
+        if entrust_no in pending_orders:
+            order_info = pending_orders[entrust_no]
+            logger.info(f"从待处理委托中移除已取消订单: {entrust_no}, 代码: {order_info.get('code', 'unknown')}")
+            del pending_orders[entrust_no]
+        
         response = {"success": True, "data": result}
         return jsonify(response), 200
     except Exception as e: