- S1: Add composite index (is_active, is_dismissed, remind_at) for
/due query performance with multi-user scaling
- W3: Snooze endpoint rejects dismissed/inactive reminders (409)
- W4: Custom field_validator on ReminderSnooze for clear error message
- S2: aria-label on all snooze/dismiss buttons in banner and toasts
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>