Fix tenant event form package selector so it no longer renders empty-value options, handles loading/empty

states, and pulls data from the authenticated /api/v1/tenant/packages endpoint.
    (resources/js/admin/pages/EventFormPage.tsx, resources/js/admin/api.ts)
  - Harden tenant-admin auth flow: prevent PKCE state loss, scope out StrictMode double-processing, add SPA
    routes for /event-admin/login and /event-admin/logout, and tighten token/session clearing semantics (resources/js/admin/auth/{context,tokens}.tsx, resources/js/admin/pages/{AuthCallbackPage,LogoutPage}.tsx,
    resources/js/admin/router.tsx, routes/web.php)

app/Mail/ContactConfirmation.php

@@ -20,7 +20,7 @@ class ContactConfirmation extends Mailable
     public function envelope(): Envelope
     {
         return new Envelope(
-            subject: 'Vielen Dank fuer Ihre Nachricht bei Fotospiel',
+            subject: __('emails.contact_confirmation.subject', ['name' => $this->name]),
         );
     }