Add support for VMIX Mixes feature
Adds support for the vmix mixes feature. A forewarning with this, is that this now means you can be stuck in preview or program even if you arent actually being previewed or programmed if your TD messes up
the TLDR of this is essentially, instead of a global preview and active, there is sub mixes that ALSO have a preview and active, so I need to check all of those and then figure out in priority if you are active, preview, or standby lol
NO AVATAR CHANGES NEEDED IF YOU HAVE A FUNCTIONING VRCTALLY SETUP ALREADY
This is purely a update to the proxy software that manages VMix -> OSC