Temporary diagnostic to answer definitively whether Discord actually delivers
video RTP to the bot when someone screen-shares / turns on camera. Both
videoReceiver and screenShareAudio rely on ssrcMap emitting videoSSRC from
voice-state updates, and NO "Video SSRC appeared"/"Screen-share video started"
lines appear even after a real share+record. This logs any RTP packet whose
payload type is not Opus (120) so we can tell: (a) video RTP IS arriving but
attribution/signaling fails, vs (b) Discord sends no video at all to a
non-signaling receiver. Remove this log once the gap is understood.