implemented search artists in MusicBrainz

HarmonyWinUI/MainWindow.xaml.cs

@@ -69,6 +69,19 @@ namespace HarmonyWinUI
 					break;
 			}
 		}
+
+		private void MainNavigation_BackRequested(NavigationView sender, NavigationViewBackRequestedEventArgs args)
+		{
+			if (MainNavigationContentFrame.CanGoBack)
+			{
+				MainNavigationContentFrame.GoBack();
+			}
+		}
+
+		private void MainNavigationContentFrame_Navigated(object sender, Microsoft.UI.Xaml.Navigation.NavigationEventArgs e)
+		{
+			MainNavigation.IsBackEnabled = MainNavigationContentFrame.CanGoBack;
+		}
 	}
 
 	public class PlayListItem