Add home hero with intro and buttons from the body, next-event card and page tiles

Elternbeirat.Web/Features/Home/Home.razor

@@ -54,7 +54,8 @@
 
 @if (_tiles.Count > 0)
 {
-    <nav class="home-tiles" aria-label="Bereiche der Website">
+    <section class="home-tiles" aria-labelledby="home-tiles-title">
+        <h2 id="home-tiles-title">Bereiche im Überblick</h2>
         <ul>
             @foreach (var tile in _tiles)
             {
@@ -70,7 +71,7 @@
                 </li>
             }
         </ul>
-    </nav>
+    </section>
 }
 
 <div class="home-embeds">