- Add WithSorting trait to POSHistory, ActivityLog, MessageLog
- Migrate GroupList and ProgramList to use WithSorting trait (remove duplicate)
- Add sortable columns (name, date, payment) to GroupShow enrollments subtable
- Add sort-header components to POS, ActivityLog, and MessageLog blade views
- Fix FK violation on group/program delete: nullify enrollments.transferred_to_id
- Fix Arabic name confirmation: normalize ي/ى, ة/ه, hamza variants before compare
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>