I did in fact find the interface without any issues but was having issues using it in any way, I got as far as telling that it needed to use the Class<T> template but was unable to figure out due to either lack of documentation or my own lack of C++ knowledge

I'll likely just stick to my own WebSocket library in the meantime until this feature is well documented/supported

With regard to your request, I confirm that we don't have in our short-term plans the WebSocket Interface to be documented. Definitively it's under our radar and you'll find more on it in future revision of the Cinema API documentation.
For the time being I encourage you to have a look to the Network section provided with the latest documentation. On my side I'll try to get back as soon as possible some code snippet showing at least the basics to use the WebSocketConnectionInterface.

Best, Riccardo