Both T-278 issues — typing '-' breaking the list, and flaky Tab-to-complete —
were resolved by the D-88 ClideTypeahead migration (T-286): the popover now
narrows live as you type (ValueNotifier-bridged suggestions) and the field keeps
focus (captureFocus:false), so '-' filters normally and Tab reliably accepts the
highlight. Add regression coverage: hyphenated queries in slash_commands_test and
a composer widget test that types through a hyphen then Tab-completes.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>