Wechsel Ticketsystem → Projekt-Admin per Einmal-Link, Rückweg-Button

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

public/admin.html

@@ -149,6 +149,7 @@
     <a class="portal-logo" href="/admin.html">Webklar <span style="opacity:.6">Admin</span></a>
     <div class="portal-header-actions">
       <span class="portal-meta" id="admin-meta"></span>
+      <a class="portal-btn-outline" href="https://ticket.webklar.com/tickets">← Ticketsystem</a>
       <button type="button" class="portal-btn-outline" id="logout-btn">Abmelden</button>
     </div>
   </header>