- Added recurrence field (daily/weekly/biweekly/monthly) to tasks schema
- Backend: auto-creates next task instance when recurring task completed
- Copies title, description, assignee, project, tags, subtasks (unchecked)
- Computes next due date based on frequency
- Optional autoActivate to immediately activate next instance
- Frontend: recurrence picker in CreateTaskModal and TaskDetailPanel
- Recurrence badges (🔄) on TaskCard, KanbanBoard, TaskPage, DashboardPage
- Schema uses JSONB column (no migration needed, db:push on deploy)