Experimental WHIP support

For those interested in testing the new WHIP protocol, here you have a PR enabling it in the mediasoup-demo (no library modifications needed):


Nice! I was also thinking about creating a Rust example of WHIP server, might use this as an example even though I am familiar with WHIP.

Basically I used some mediasoup-client libraries at server side for parsing the SDP request sent in the WHIP request and create the answer, as done in the mediasoup-client Device class.