refactor external orders

frontend/src/pages/LieferantDetail.tsx

@@ -26,6 +26,12 @@ import type { LieferantFormData } from '../types/bestellung.types';
 
 const emptyForm: LieferantFormData = { name: '', kontakt_name: '', email: '', telefon: '', adresse: '', website: '', notizen: '' };
 
+function ensureUrl(url: string): string {
+  if (!url) return url;
+  if (url.startsWith('http://') || url.startsWith('https://')) return url;
+  return `https://${url}`;
+}
+
 export default function LieferantDetail() {
   const { id } = useParams<{ id: string }>();
   const navigate = useNavigate();
@@ -265,7 +271,7 @@ export default function LieferantDetail() {
             <Card variant="outlined"><CardContent>
               <Typography variant="caption" color="text.secondary">Website</Typography>
               <Typography>
-                {vendor!.website ? <a href={vendor!.website} target="_blank" rel="noopener noreferrer">{vendor!.website}</a> : '–'}
+                {vendor!.website ? <a href={ensureUrl(vendor!.website)} target="_blank" rel="noopener noreferrer">{vendor!.website}</a> : '–'}
               </Typography>
             </CardContent></Card>
           </Grid>