The 4 im query commands had three inconsistent sort conventions and leaked upstream API jargon (ByCreateTimeAsc, member_count_desc) directly to users. This PR unifies them on a single rule — --sort selects a field, --order selects a direction, both from fixed enums — so an agent only ever picks from an enum, never constructs a string. Old flags (--sort-type, --sort-by, and --sort on messages/threads) are kept as hidden silent aliases (no deprecation warning), so existing scripts keep working byte-for-byte.