feat: add rent-due share page for rent payment information

Created a new /share/rent-due/ page to display rent payment information
separately from utility bills.

Changes:
- Created /share/rent-due/[id]/ page structure with RentViewPage component
- Created ViewRentCard component to display rent amount and payment info
- Added uploadRentProofOfPayment action for tenant proof upload
- Added translation keys for rent-specific labels (en/hr)
- Updated rent email templates to link to /share/rent-due/ instead of /share/bills-due/
- Updated documentation to reflect new URL structure

The rent page displays:
- Rent amount
- IBAN or Revolut payment information with QR/barcode
- Rent proof of payment upload (when enabled)

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

sprints/email-worker.md

@@ -113,7 +113,7 @@ Address: BillingLocation-tenantEmail
 
 <p>Your rent for the apartment ${location.name} is due today.</p>
 
-<p>For details and payment options please click the following link: <a href="https://rezije.app/share/bills-due/${shareId}">Rent details</a></p>
+<p>For details and payment options please click the following link: <a href="https://rezije.app/share/rent-due/${shareId}">Rent details</a></p>
 
 <p>Thank you!</p>