Populate navigation caterogies

Wallet.Avalonia/CategoryNavigationView.axaml.cs

@@ -0,0 +1,10 @@
+using Toolkit.UI.Controls.Avalonia;
+
+namespace Wallet.Avalonia;
+
+public partial class CategoryNavigationView :
+    NavigationViewItem
+{
+    public CategoryNavigationView() =>
+        InitializeComponent();
+}