FEAT: Implement deceased/givenaway enclosure visibility rules, preserve external clan name, and hide receiver fields for deceased gerbils

gerbil-manager-web/src/pages/KontaktDetailPage.tsx

@@ -96,6 +96,17 @@ export default function KontaktDetailPage() {
       {deleteError && <div className="alert alert--error">{deleteError}</div>}
 
       <dl className="def-list">
+        <div className="def-row">
+          <dt>Rolle</dt>
+          <dd>
+            {[
+              c.isBreeder ? 'Züchter' : null,
+              c.isReceiver ? 'Abnehmer' : null,
+            ]
+              .filter(Boolean)
+              .join(' · ') || '—'}
+          </dd>
+        </div>
         <div className="def-row">
           <dt>{t.fields.email}</dt>
           <dd>{c.email ?? '—'}</dd>