应用: 拼多多
任务: 打开拼多多，搜索“沙发”，选择第四个商品，加入购物车
操作步骤:
step_id: 0
action: CLICK
step_id: 1
action: CLICK
step_id: 2
action: TYPE
type_text: 沙发
step_id: 3
action: CLICK
step_id: 4
action: CLICK
step_id: 5
action: CLICK