collaboration_share and collaboration_access_request (requesters see only table and id; non-readers get a notification without record data); collaboration_task with reminders and overdue notices, Mark done/Reopen; collaboration_record_assignment with Assign to / Take ownership bulk actions; MyWorkService summary (open tasks, records assigned, unread mentions); home cards; parent cleanup. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>