I'm gathering open source ChatGPT UIs at: https://github.com/itsuka-dev/awesome-chatgpt-ui

I think the UI that best meets your requirements is https://github.com/WongSaang/chatgpt-ui (django backend, multiple user auth, streaming support)

If you find a better UI that is not on the list, I would appreciate it if you could let me know so that I can update the list.