Support jacktrip 1.3 broadcast mode

[madwort]

So, when we've successfully switched to 1.3, we should start using broadcast mode - https://groups.google.com/g/jacktrip-users/c/SL0dGus9ls0
It will mean more panning plugins, as we'll need to do a whole second set of plugins that route broadcast_* to pan to darkice* for the broadcast.
We currently usually run this at settings that make the audio completely clear, so I'm not sure what this would mean for us - the advantage would be that we could run at more aggressive settings to reduce latency for the musicians but still have a clear output going to the icecast listeners.

[sandreae]

Think this would be great to try. Would mean the recordings would have less glitching too 👍

[madwort]

yeah!!

[madwort]

I guess it'll increase memory usage, but probably not by a problematic amount in modern terms?!