Use Command highlighting state for composer menu navigation

- Switch composer menu arrow-key navigation to `Command`'s internal highlight handling
- Track highlighted item by id instead of manual index/keyboard state
- Remove custom hover/highlight plumbing and hidden-scroll sync logic
2136fee923Julius Marminge committed on 2/18/2026, 2:41:28 AMparentb73b2c9
1 file changedLine totals unavailable