Add a second virtual SS tile on RN when a remote participant that has multi-stream mode enabled starts a screenshare.

* fix(multi-stream) update selector to find ss track by videoType or mediaType

* ref(multi-stream) move fake ss creation logic and support video type changed

* refactor(multi-stream) decouple sending and receiving multiple screenshare streams

* fix(multi-stream) fix receiver constraints with signaling and without multi-stream

* fix(mutli-stream) ensure plan b original SS thumbnail displays avatar

* fix(multi-stream) show fake SS for plan b sender

* refactor(multi-stream) poc for moving SS creation to state listener

* remove reference to fake SS creation

* fix lint errors

* rename to virtual screenshare participants

* fix minor bugs

* rename participant subscriber to specify web support only