Consolidate mute logic
At the moment, we have two distinct handlers for the 'muted' state: one for the floor channel, which is the native BBB implementation, and another one for the interpretation channels, which is only active when a speaker joins an interpretation channel. When switching between an interpretation channel and the floor channel, we change the mute states accordingly, so the mute logic works correctly, but an interpreter is displayed as muted by the native handler. This causes confusion for some users who believe to be muted when they, in fact, are not.
There should be one mute logic for all channels, floor as well as interpretation.