- Reworked the tenant admin login page

- Updated the User model to implement Filament’s tenancy contracts
- Seeded a ready-to-use demo tenant (user, tenant, active package, purchase)
- Introduced a branded, translated 403 error page to replace the generic forbidden message for unauthorised admin hits
- Removed the public “Register” links from the marketing header
- hardened join event logic and improved error handling in the guest pwa.

resources/js/admin/pages/EventFormPage.tsx

@@ -197,14 +197,17 @@ export default function EventFormPage() {
                   />
                 </div>
                 <div className="space-y-2">
-                  <Label htmlFor="event-slug">Slug / URL-Endung</Label>
+                  <Label htmlFor="event-slug">Slug / interne Kennung</Label>
                   <Input
                     id="event-slug"
                     placeholder="sommerfest-2025"
                     value={form.slug}
                     onChange={(e) => handleSlugChange(e.target.value)}
                   />
-                  <p className="text-xs text-slate-500">Das Event ist spaeter unter /e/{form.slug || 'dein-event'} erreichbar.</p>
+                  <p className="text-xs text-slate-500">
+                    Diese Kennung wird intern verwendet. Gaeste erhalten Zugriff ausschliesslich ueber Join-Tokens und deren
+                    QR-/Layout-Downloads.
+                  </p>
                 </div>
                 <div className="space-y-2">
                   <Label htmlFor="event-date">Datum</Label>