Add clipboard writer

Toolkit.Avalonia/ClipboardWriter.cs

@@ -0,0 +1,23 @@
+using Avalonia.Controls;
+using Avalonia.Input.Platform;
+using Toolkit.Foundation;
+
+namespace Toolkit.Avalonia;
+
+public class ClipboardWriter(ITopLevelProvider topLevelProvider) :
+    IClipboardWriter
+{
+    public async Task Write<TContent>(TContent content)
+    {
+        if (topLevelProvider.Get() is TopLevel topLevel)
+        {
+            if (topLevel.Clipboard is IClipboard clipboard)
+            {
+                if (content is string stringContent)
+                {
+                    await clipboard.SetTextAsync(stringContent);
+                }
+            }
+        }
+    }
+}

Toolkit.Avalonia/IServiceCollectionExtensions.cs

@@ -127,6 +127,8 @@ public static class IServiceCollectionExtensions
         services.AddTransient<ITopLevelProvider, TopLevelProvider>();
         services.AddTransient<IFileProvider, FileProvider>();
 
+        services.AddTransient<IClipboardWriter, ClipboardWriter>();
+
         services.AddTransient<IImageReader,  ImageReader>();
         services.AddTransient<IImageWriter, ImageWriter>();
         services.AddTransient<IImageResizer, ImageResizer>();
@@ -154,6 +156,8 @@ public static class IServiceCollectionExtensions
                 services.AddTransient<ITopLevelProvider, TopLevelProvider>();
                 services.AddTransient<IFileProvider, FileProvider>();
 
+                services.AddTransient<IClipboardWriter, ClipboardWriter>();
+
                 services.AddTransient<IImageReader, ImageReader>();
                 services.AddTransient<IImageWriter, ImageWriter>();
                 services.AddTransient<IImageResizer, ImageResizer>();

Toolkit.Foundation/IClipboardWriter.cs

@@ -0,0 +1,6 @@
+namespace Toolkit.Foundation;
+
+public interface IClipboardWriter
+{
+    Task Write<TContent>(TContent content);
+}