- Add /share/attachment/.* to public pages in middleware.ts
- Create new /share/attachment/[id] route handler for downloading attachments without authentication
- Add custom 404 page for missing shared attachments
- Update ViewBillCard component to use shared attachment route instead of authenticated route
This enables attachment downloads from shared bill pages without requiring user login.
🤖 Generated with [Claude Code](https://claude.ai/code)
Co-Authored-By: Claude <noreply@anthropic.com>
