feat: conditional navbar — shows username/logout when logged in

app/templates/base.html

@@ -28,10 +28,19 @@
       {{ item.label }}
     </a>
     {% endfor %}
-    <div class="ml-auto">
-      <button class="text-white text-sm px-4 py-1.5 rounded border border-white/40 bg-white/15 hover:bg-white/25">
-        Anmelden
-      </button>
+    <div class="ml-auto flex items-center gap-3">
+      {% if current_user | default(None) %}
+        <span class="text-white/85 text-sm">{{ current_user.username }}</span>
+        <a href="/auth/logout"
+           class="text-white text-sm px-4 py-1.5 rounded border border-white/40 bg-white/15 hover:bg-white/25">
+          Abmelden
+        </a>
+      {% else %}
+        <a href="/auth/login"
+           class="text-white text-sm px-4 py-1.5 rounded border border-white/40 bg-white/15 hover:bg-white/25">
+          Anmelden
+        </a>
+      {% endif %}
     </div>
   </nav>
 
@@ -46,4 +55,4 @@
   </footer>
 
 </body>
-</html>
+</html>