feat: add email verification check to unsubscribe page

Security Enhancement:
- Server-side validation of email status before allowing unsubscribe
- Only allow unsubscribing from verified emails
- Show "Action Not Allowed" message for unverified/unsubscribed emails
- Extract and validate share-id on server side
- Return 404 for invalid share-ids or missing tenant emails

Implementation:
- Convert page.tsx to async server component
- Fetch location and check tenantEmailStatus
- Pass isVerified prop to client component
- Add bilingual "not-allowed" translations

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

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

web-app/app/[locale]/email/unsubscribe/[id]/EmailUnsubscribePage.tsx

@@ -7,9 +7,10 @@ import { CheckCircleIcon } from '@heroicons/react/24/outline';
 
 interface EmailUnsubscribePageProps {
     shareId: string;
+    isVerified: boolean;
 }
 
-export default function EmailUnsubscribePage({ shareId }: EmailUnsubscribePageProps) {
+export default function EmailUnsubscribePage({ shareId, isVerified }: EmailUnsubscribePageProps) {
     const t = useTranslations('email-unsubscribe-page');
     const [isUnsubscribing, setIsUnsubscribing] = useState(false);
     const [isUnsubscribed, setIsUnsubscribed] = useState(false);
@@ -61,6 +62,17 @@ export default function EmailUnsubscribePage({ shareId }: EmailUnsubscribePagePr
         );
     }
 
+    if (!isVerified) {
+        return (
+            <div className="card bg-base-100 shadow-xl max-w-2xl mx-auto mt-8">
+                <div className="card-body">
+                    <h2 className="card-title text-warning">{t('not-allowed.title')}</h2>
+                    <p>{t('not-allowed.message')}</p>
+                </div>
+            </div>
+        );
+    }
+
     return (
         <div className="card bg-base-100 shadow-xl max-w-2xl mx-auto mt-8">
             <div className="card-body">

web-app/app/[locale]/email/unsubscribe/[id]/page.tsx

@@ -1,12 +1,44 @@
 import { Suspense } from 'react';
 import EmailUnsubscribePage from './EmailUnsubscribePage';
 import { Main } from '@/app/ui/Main';
+import { getDbClient } from '@/app/lib/dbClient';
+import { BillingLocation, EmailStatus } from '@/app/lib/db-types';
+import { extractShareId, validateShareChecksum } from '@/app/lib/shareChecksum';
+import { notFound } from 'next/navigation';
 
 export default async function Page({ params: { id } }: { params: { id: string } }) {
+    // Extract and validate share ID
+    const extracted = extractShareId(id);
+    if (!extracted) {
+        notFound();
+    }
+
+    const { locationId, checksum } = extracted;
+
+    // Validate checksum
+    if (!validateShareChecksum(locationId, checksum)) {
+        notFound();
+    }
+
+    // Fetch location to check email status
+    const dbClient = await getDbClient();
+    const location = await dbClient.collection<BillingLocation>("lokacije")
+        .findOne(
+            { _id: locationId },
+            { projection: { tenantEmail: 1, tenantEmailStatus: 1 } }
+        );
+
+    if (!location || !location.tenantEmail) {
+        notFound();
+    }
+
+    // Check if email is verified
+    const isVerified = location.tenantEmailStatus === EmailStatus.Verified;
+
     return (
         <Main>
             <Suspense fallback={<div className="text-center p-8">Loading...</div>}>
-                <EmailUnsubscribePage shareId={id} />
+                <EmailUnsubscribePage shareId={id} isVerified={isVerified} />
             </Suspense>
         </Main>
     );

web-app/messages/en.json

@@ -482,6 +482,10 @@
     "error": {
       "title": "Unsubscribe Failed",
       "unknown": "An error occurred while unsubscribing. Please try again or contact your landlord."
+    },
+    "not-allowed": {
+      "title": "Action Not Allowed",
+      "message": "You can only unsubscribe from verified email addresses. This email address has not been verified yet or has already been unsubscribed."
     }
   },
   "privacy-policy-page": {

web-app/messages/hr.json

@@ -479,6 +479,10 @@
     "error": {
       "title": "Odjava Nije Uspjela",
       "unknown": "Došlo je do greške prilikom odjave. Molimo pokušajte ponovno ili kontaktirajte vašeg vlasnika nekretnine."
+    },
+    "not-allowed": {
+      "title": "Akcija Nije Dopuštena",
+      "message": "Možete se odjaviti samo s potvrđenih email adresa. Ova email adresa još nije potvrđena ili je već odjavljena."
     }
   },
   "privacy-policy-page": {