Added more UI logic. Added a manga pipeline test.

MangaReader.WinUI/Converters/UppercaseConverter.cs

@@ -0,0 +1,20 @@
+using Microsoft.UI.Xaml.Data;
+using System;
+
+namespace MangaReader.WinUI.Converters;
+
+public partial class UppercaseConverter : IValueConverter
+{
+    public object? Convert(object value, Type targetType, object parameter, string language)
+    {
+        if (value == null)
+            return null;
+
+        return value.ToString().ToUpperInvariant();
+    }
+
+    public object ConvertBack(object value, Type targetType, object parameter, string language)
+    {
+        throw new NotImplementedException();
+    }
+}