Two interesting updates! The nesting feature and the app preview feature are now live! 😊（两个有趣的更新！套娃功能和APP预览功能已上线！）

[heshengtao]

Two interesting updates!

1. Introduced a cool nesting feature for everyone. You need to disable the main_brain property of the LLM node, which allows you to use this LLM node as a tool. Link this node’s tool to another normal LLM, and you’ll find that the other LLM can call it like a tool!
   给大家带来了一个很酷的套娃功能，你需要将LLM节点的main_brain属性disable，就可以把这个LLM节点当作tool使用，将这个节点的tool链接到另一个正常的LLM上，就会发现，另一个LLM可以像工具一样调用它！

2. New start_workflow and end_workflow nodes have been added. You can use these two nodes to define the start and end points of your workflow. Place your workflow in the workflow subfolder under this project folder. Then, click on setup_streamlit_app.bat in the project folder. In the Streamlit interface, click on settings and replace it with your workflow.
   新增了start_workflow和end_workflow节点，你可以用这个两个节点来定义工作流的起点和终点，将你的工作流放到本项目文件夹下的workflow子文件夹，然后在本项目文件夹下点击setup_streamlit_app.bat，在streamlit的界面中，点击设置，替换为你的工作流。