RTCQuicRole should support a "client-browser" role

[unicomp21]

There should be some process where RTCQuicRole.client can be converted to a "local only" browser url which opens in another browser tab. We could call it RTCQuicRole.client-browser. Having such a capability would open up multiple use cases.

The one I'm most interested in would be vpn clients. With websocket and RTCDataChannel we now have a couple ways to "tunnel" vpn packets, the remaining problem is having a way to peel off the outer layers, such as wireguard, etc., within a browser process which is essentially acting as a "web server" within a "web page", or maybe I should call it a vpn proxy/web server/web page. From this "vpn proxy/web server/web page" we can launch a "single" connection (via a special url) which proxies http3/quic traffic for another browser tab which then provides a normal browser experience within the vpn.

To simplify all of the above. The intention would be running a special/local "web server" within a browser page/tab. From this tab, through opening a special url, other tabs could be spawned which are connected to the local web web server, RTCQuicRole.client-browser. The local web server can then proxy traffic over vpn connections being tunneled via websocket or rtcdatachannel.

[unicomp21]

Another possibility, similar to the above, would be essentially running a "socks proxy" within a web page/browser tab, which tunnels packets thru websocket or rtcdatachannel. It could then spawn off other browser tabs via a special url, which have all their packets tunneled thru the launching page (which is running the socks proxy).