- TrackerPage: confirm('Mark as paid?') → AlertDialog with dynamic bill name
- DataPage: window.confirm('Import SQLite?') → AlertDialog for import confirmation
- Both dialogs use proper shadcn/ui components (AlertDialogAction/Cancel)
- Theme-aware, accessible, consistent with app design system
- STRUCTURE.md: corrected tech stack (Vite+React, not Next.js)
- Version bumped to 0.23.3
- Backend: previous month calculation with year wrapping (Jan→Dec)
- Backend: previous_month_paid per bill row, previous_month_total in summary
- Frontend: 'Last Month' column in desktop table with muted text
- Frontend: 'Last Month' in mobile view, summary card for prev month total
- Hudson security audit: 5/5 PASS (SQL injection, date wrapping, user scoping, auth, XSS)