Initial porting attempt of my WinForms MVVM library to Avalonia; added IWindowScope as a new reature because this library should support Microsoft's dependency injector

Source/Messages/IMessageService.cs

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+#region Apache License 2.0
+/*
+Nuclex Foundation libraries for .NET
+Copyright (C) 2002-2025 Markus Ewald / Nuclex Development Labs
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+#endregion // Apache License 2.0
+
+using System;
+using System.Threading.Tasks;
+
+using MessageBoxIcon = MsBox.Avalonia.Enums.Icon;
+using MessageBoxButtons = MsBox.Avalonia.Enums.ButtonEnum;
+using MessageDialogResult = MsBox.Avalonia.Enums.ButtonResult;
+
+namespace Nuclex.Avalonia.Messages {
+
+  /// <summary>Performs simple user interaction</summary>
+  /// <remarks>
+  ///   Methods provided by this service can be covered using plain old message boxes
+  ///   and do not require special dialogs or calls to the task dialog API.
+  /// </remarks>
+  public interface IMessageService {
+
+    /// <summary>Triggered when a message is about to be displayed to the user</summary>
+    event EventHandler<MessageEventArgs> MessageDisplaying;
+
+    /// <summary>Triggered when the user has acknowledged the current message</summary>
+    event EventHandler MessageAcknowledged;
+
+    /// <summary>Asks the user a question that can be answered via several buttons</summary>
+    /// <param name="image">Image that will be shown on the message box</param>
+    /// <param name="text">Text that will be shown to the user</param>
+    /// <param name="buttons">Buttons available for the user to click on</param>
+    /// <returns>The button the user has clicked on</returns>
+    Task<MessageDialogResult> ShowQuestionAsync(
+      MessageBoxIcon image, MessageText text, MessageBoxButtons buttons
+    );
+
+    /// <summary>Displays a notification to the user</summary>
+    /// <param name="image">Image that will be shown on the message bx</param>
+    /// <param name="text">Text that will be shown to the user</param>
+    Task ShowNotificationAsync(MessageBoxIcon image, MessageText text);
+
+  }
+
+} // namespace Nuclex.Avalonia.Messages