support new/modern Matrix Call

[wrenix]

Feature Description

• MSC3401: MSC3401: Native Group VoIP Signalling matrix-org/matrix-spec-proposals#3401
• MSC4075: MSC4075: MatrixRTC m.rtc.notification Call Ringing and Notifications matrix-org/matrix-spec-proposals#4075

That is the basic of Element-Call and the new Element-X client (where is it supported already. Like in Element-Web and starting in hydrogen-web).

Rationale

It become the new standard of calling

Mockup

No response

Additional Context

No response