Improve the Ui part and provide drag and drop operation of data stream

[QiuYilin]

The most intuitive way is to introduce the imgui-node-editor library

[QiuYilin]

The key to using imgui-node-editor is to need node id and pin id. There are two ways to do this. One is to modify the code in the core folder and add pin id to the core code. The other is to build an id mechanism based on the node pointer and port index through std::hash.In addition, the app in imgui-node-editor is worth learning from, as it abstracts the backend of imgui very well.