Group rename WIP

src/GuiApp/Avalonia/FileTime.GuiApp/Converters/TextDecorationConverter.cs

@@ -0,0 +1,16 @@
+using System.Globalization;
+using Avalonia.Data.Converters;
+using Avalonia.Media;
+
+namespace FileTime.GuiApp.Converters;
+
+public class TextDecorationConverter : IValueConverter
+{
+    public object? Convert(object? value, Type targetType, object? parameter, CultureInfo culture)
+    {
+        if (value is bool b && b) return TextDecorations.Underline;
+        return null;
+    }
+
+    public object? ConvertBack(object? value, Type targetType, object? parameter, CultureInfo culture) => throw new NotImplementedException();
+}