chore: revert Dashboard ViewHeaderContent removing

Author: DevTKSS

src/DevTKSS.Uno.Samples.MvuxGallery/Presentation/ViewModels/DashboardModel.cs

@@ -112,7 +112,22 @@ public async ValueTask SwitchCodeSampleAsync([FeedParameter(nameof(SelectedOptio
 
     #endregion
 
-
+    #region ViewHeaderContent
+    /// <summary>
+    /// Gets the header content for the view, including an image and caption.
+    /// </summary>
+    /// <remarks>
+    /// A Feed always needs a Async or Create function wich takes the cancellation token as parameter.<br/>
+    /// So this is using a Task.Delay to simulate a delay in the async function.
+    /// </remarks>
+    public IFeed<HeaderContent> ViewHeaderContent => Feed<HeaderContent>.Async(
+           valueProvider: async (ct) =>
+           {
+               await Task.Delay(1, ct);
+               return new HeaderContent(ImageLocation: "Assets/Images/styled_logo.png",
+                              Caption: _stringLocalizer["ListViewTitle"]);
+           });
+    #endregion
 
 }