chore: rename demo files.

src/Shared/HandyControlDemo_Shared/UserControl/Controls/ButtonGroupDemo.xaml.cs

@@ -0,0 +1,39 @@
+using System.Windows;
+using System.Windows.Media.Imaging;
+
+namespace HandyControlDemo.UserControl;
+
+public partial class ButtonGroupDemoCtl
+{
+    public ButtonGroupDemoCtl()
+    {
+        InitializeComponent();
+    }
+
+    public static readonly DependencyProperty SourceProperty = DependencyProperty.Register(
+        "Source", typeof(BitmapFrame), typeof(Avatar), new PropertyMetadata(default(BitmapFrame)));
+
+    public BitmapFrame Source
+    {
+        get => (BitmapFrame) GetValue(SourceProperty);
+        set => SetValue(SourceProperty, value);
+    }
+
+    public static readonly DependencyProperty UserNameProperty = DependencyProperty.Register(
+        "DisplayName", typeof(string), typeof(Avatar), new PropertyMetadata(default(string)));
+
+    public string DisplayName
+    {
+        get => (string) GetValue(UserNameProperty);
+        set => SetValue(UserNameProperty, value);
+    }
+
+    public static readonly DependencyProperty LinkProperty = DependencyProperty.Register(
+        "Link", typeof(string), typeof(Avatar), new PropertyMetadata(default(string)));
+
+    public string Link
+    {
+        get => (string) GetValue(LinkProperty);
+        set => SetValue(LinkProperty, value);
+    }
+}