Suport for simulcast codec of audio. (#1207)

* Suport for simulcast codec of audio.

Note that a disable should be a mute on client side and not a track
stop to allow re-enabling the track again.

* generated protobuf

* name change

* generated protobuf

* Create young-mayflies-wash.md

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Co-authored-by: github-actions <41898282+github-actions[bot]@users.noreply.github.com>

Author: boks1971

.changeset/young-mayflies-wash.md

@@ -0,0 +1,5 @@
+---
+"@livekit/protocol": patch
+---
+
+Suport for simulcast codec of audio.