"Muted" actor flag

[JPL]

Right now if I want to mute (never play any sounds for any reason) a monster from mod code, I have to do some combination of set its SeeSound DeathSound etc, override any functions eg special melee or attack functions that call something like A_PlaySound, or blank out any SNDINFO definitions for sounds they make (which renders those sounds silent for all contexts, not just the one actor).
It would be useful to be able to flag any specific actor as "muted", eg bMuted in ZScript, such that any sound they try to play, doesn't.

I'm not super familiar with the code path for actors playing sounds but the A_PlaySound definition in p_actionfunctions.cpp seems like the logical place to add the check for this new flag.