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>

web-app/app/[locale]/share/rent-due/[id]/page.tsx

@@ -0,0 +1,14 @@
+import { Suspense } from 'react';
+import RentViewPage from './RentViewPage';
+import { Main } from '@/app/ui/Main';
+import { LocationEditFormSkeleton } from '@/app/ui/LocationEditForm';
+
+export default async function Page({ params: { id } }: { params: { id: string } }) {
+    return (
+        <Main>
+            <Suspense fallback={<LocationEditFormSkeleton />}>
+                <RentViewPage shareId={id} />
+            </Suspense>
+        </Main>
+    );
+}