I would like to start (maybe a discussion is the best channel) to get a status on what per the protocol is required and what is not working. You mention WebSockets not working but that's not actually a listed transport on other implementations so it would seem a very important "nice to have", but I would like to get more clarity (without reading the source line by line) on what is missing from base implementation so I could roll up my sleeves and start working on it.
I'd love to figure out a way to get this to complete enough to fully interoperate with TypeScript and Python implementations both as a client/server and host.