Changes:
- Secure uploadUtilBillsProofOfPayment with checksum validation
- Update ViewLocationCard to accept and use shareId prop
- Update ViewBillCard to accept shareId and use it for uploads
- Update ViewBillBadge to pass shareId to bill detail pages
- Add client-side validation check for shareId before upload
- Update back button links to use shareId
Security improvements:
- Both per-bill and combined uploads now validate checksum and TTL
- IP-based rate limiting applied to both upload types
- PDF magic bytes validation for both upload types
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>
