Voice channel move: user disappears from list but audio still plays in original channel

Additional data point from testing: the bug is not reproducible for every user. With the affected user it behaves like this: the first move (drag to another voice channel) works and the user visibly lands in the destination channel, but on a second consecutive move the user vanishes from the member list while their audio remains audible in the previous channel (and is not heard in the new one). So the failure seems tied to the state accumulated per-session (LiveKit room/connection) rather than to the move action itself — a fresh/healthy client survives the first transfer but a second transfer breaks it.