Users see upcoming recurring tasks in area view

Priority: High

Estimated Effort: M (2-3 days)

User Value

Users immediately see their recurring tasks appearing regularly in area task lists instead of tasks "disappearing" after creation.

Problem Context

Currently, when users create recurring tasks, only the first instance appears in task lists. Subsequent instances only appear after completing the previous one, making the app feel broken and not matching user expectations from other task management tools.

Solution Approach

Implement lazy persistence - generate virtual instances on-demand for display while persisting them only when users interact with them.

Acceptance Criteria

• [ ] Area task view shows 7 days of upcoming instances for active recurring templates
• [ ] Generated instances appear alongside existing persisted instances in chronological order
• [ ] Users can mark generated instances as complete (they get persisted automatically)
• [ ] Completing a generated instance triggers normal next-instance generation
• [ ] Generated instances have proper due dates based on recurrence patterns

Technical Scope

• Files: app/area/[id]/area-content.tsx, components/custom/task-list.tsx, lib/recurring-tasks.ts
• Dependencies: Uses existing calculateNextOccurrence() function
• Integration: Area task display, task completion API, database persistence

Out of Scope

• Project task views (handled in separate issue)
• Advanced task editing on virtual instances
• Bulk operations on virtual instances

Implementation Notes

• Extend task queries to include both persisted instances AND generated virtual instances from active templates
• Virtual instances become "real" instances when users interact with them (completion, editing)
• Use existing recurrence calculation logic from lib/recurrence.ts

INVEST Check

✅ Independent - Can be implemented without waiting for other work
✅ Negotiable - Implementation details can be adjusted
✅ Valuable - Directly fixes the core user experience bug
✅ Estimable - Clear scope, 2-3 days of work
✅ Small - Focused on area view context only
✅ Testable - Clear acceptance criteria for verification