Cover the last remaining interfaces across libraries/audio, libraries/cachestore,
libraries/indicator, libraries/slashcommands, libraries/voiceplayer and
services/apperror, with their members and parameters.
This completes the effort: all 222 in-scope interfaces and their 820 members in
the 60 api modules that hold any now carry documentation.
Notable points: CacheStore applies no expiry of its own and only records when each
entry was written, leaving staleness to the caller; SlashCommandService.parse
never throws, returning NotACommand for ordinary text and an error case for a
malformed command.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Benoit Marty