Permanent mute

[PVince81]

• [x] Requires permissions as a base, ref https://github.com/nextcloud/spreed/issues/931

Is your feature request related to a problem? Please describe. In a conversation with many participants it might be necessary to mute people when too much talking is happening in the background and disturbing a presentation. There's already a force mute feature, but after muting, people can still unmute themselves again. A moderator might want to permanently lock the mute state for all participants until it's their turn to speak.

Describe the solution you'd like

• A new call option "Participants cannot unmute themselves, only moderators can" that could be used for such meetings.

  • The option would be visible in the three dots menu and specific for the current call and can be changed during the call, to switch modes.
  • Optionally, that new option could have a default for a given conversation (like a classroom)

• A moderator can manually "ask to unmute" anyone in this mode to give them a voice.

• If someone wants to speak, they can raise a hand

[wiswedel]

The same should apply for video and screen sharing.

[nickvergessen]

So the functionality is now there with #931

I would still leave this open as the icon in the call view is still only a temporary mute and I guess we need a quick access for that.