Move common things to AppCore from GuiApp

src/GuiApp/Avalonia/FileTime.GuiApp.App/Extensions/KeyEventArgsExtension.cs

@@ -0,0 +1,18 @@
+using Avalonia.Input;
+using FileTime.App.Core.Models;
+using FileTime.App.Core.Services;
+
+namespace FileTime.GuiApp.App.Extensions;
+
+public static class KeyEventArgsExtension
+{
+    public static GeneralKeyEventArgs? ToGeneralKeyEventArgs(this KeyEventArgs args, IAppKeyService<Key> appKeyService)
+    {
+        var maybeKey = appKeyService.MapKey(args.Key);
+        if (maybeKey is not {} key1) return null;
+        return new GeneralKeyEventArgs(h => args.Handled = h)
+        {
+            Key = key1
+        };
+    }
+}