use modern async backend #315
Description
Is your feature request related to a problem? Please describe.
Currently gdbgui's backend uses SocketIO and has a dependency on gevent, an older async implementation. Additionally, SocketIO is not needed in all websocket implementations.
Describe the solution you'd like
Use a modern async backend that does not require gevent/eventlet, nor SocketIO. A good candidate is FastAPI. Another is Starlette, which FastAPI is based on.