Added playing song info view and view model.

Harmonia.UI/Views/PlayingSongInfo.axaml.cs

@@ -0,0 +1,17 @@
+using Avalonia.Controls;
+using Avalonia.Input;
+using Avalonia.Interactivity;
+using Harmonia.UI.ViewModels;
+
+namespace Harmonia.UI.Views;
+
+public partial class PlayingSongInfo : UserControl
+{
+    private readonly PlayingSongInfoViewModel _viewModel;
+
+    public PlayingSongInfo()
+    {
+        InitializeComponent();
+        _viewModel = (PlayingSongInfoViewModel)DataContext!;
+    }
+}