RackGetInfo reports the rack's handles, buffer, id, uid, option limits,
render count and active voices. VoiceGetPortInfo reports a port's matrix,
volume and destination. VoiceQueryInfo answers info id 0x4001 with the
voice channel count and throws for other ids. Assumptions are recorded in
TechnicalDebt.
Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>