Add InfoEvent with confirmation

Jugenddienst Stunden/Models/ConfirmationEventArgs.cs

@@ -0,0 +1,21 @@
+
+using System.Threading.Tasks;
+
+namespace Jugenddienst_Stunden.Models;
+public sealed class ConfirmationEventArgs : System.EventArgs {
+	public string Title { get; }
+	public string Message { get; }
+	public string ConfirmText { get; }
+
+	private readonly TaskCompletionSource<bool> _tcs = new();
+
+	public ConfirmationEventArgs(string title, string message, string confirmText = "OK") {
+		Title = title;
+		Message = message;
+		ConfirmText = confirmText;
+	}
+
+	public Task<bool> Task => _tcs.Task;
+
+	public void SetResult(bool result) => _tcs.TrySetResult(result);
+}