Scene/source builder with image overlays, reuse dialog, and SQLite layout persistence

Helpers/NotNullToVisibilityConverter.cs

@@ -0,0 +1,14 @@
+using System.Globalization;
+using System.Windows;
+using System.Windows.Data;
+
+namespace ytLive.Helpers;
+
+public class NotNullToVisibilityConverter : IValueConverter
+{
+    public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
+        => value != null ? Visibility.Visible : Visibility.Collapsed;
+
+    public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
+        => value is Visibility.Visible;
+}