Mark Appointments as No-Show Directly on the Calendar

There's no built-in way to mark a missed appointment as a no-show directly on the calendar event; the only record lives in the chart note, so the calendar itself doesn't visually reflect no-shows. Suggested fix: add a "No-Show" status option on calendar events themselves (similar to Cancelled), which could also auto-link to the no-show chart note for a unified record.