CR-1: Path traversal in createReceiptZip — validate image_path is within storage/
CR-2: Missing authz on EditExpense/UpdateExpense — verify event ownership
CR-3: OTP timing side-channel — use crypto/subtle.ConstantTimeCompare
CR-4: Logout doesn't invalidate session — moved to AuthHandler with Sessions.Delete()
CR-5: OTP reuse race condition — mutex lock around validate+delete
CR-6: Live credentials on disk — removed .env from disk entirely
CR-7: No TLS — documented as expected behind-proxy deployment
Additional:
- Removed stale github.com/expenseflow import path from auth.go
- Made EnvironmentFile optional (prefix with -) so .env is not required
- App runs and starts clean without any .env file
- Passwordless email OTP authentication
- Event-based expense tracking with HTMX UI
- AI receipt extraction via DeepSeek Vision API
- CSV/PDF report generation with email filing
- PWA with service worker and manifest
- Mobile-first responsive design
- SQLite database with auto-migration
