Reintroduced events as [Obsolete]

The `DeleteEvent`, `MoveEvent`, and `RenameEvent` were renamed to, respectively, `TopicDeleted`, `TopicMoved, and `TopicRenamed`. This provides instructions to callers of the original class name.

Unfortunately, an `[Obsolete[]` member of an interface still needs to be implemented on each implementation of that interface. As such, we won't want to persist these for long after the migration to OnTopic 5.0.0. That said, fortunately, we expect all implementations of `ITopicRepository` to implement `ObservableTopicRepository` as a base class and, therefore, can implement these in that one location in order to cover all derived types (e.g., `SqlTopicRepository`, `CachedTopicRepository`, &c.)

Author: JeremyCaney

OnTopic/Repositories/ITopicRepository.cs

@@ -56,6 +56,18 @@ public interface ITopicRepository {
     /// </summary>
     event EventHandler<TopicRenameEventArgs> TopicRenamed;
 
+    /// <inheritdoc cref="TopicDeleted"/>
+    [Obsolete("The DeleteEvent has been renamed to TopicDeleted")]
+    event EventHandler<DeleteEventArgs> DeleteEvent;
+
+    /// <inheritdoc cref="TopicMoved"/>
+    [Obsolete("The MoveEvent has been renamed to TopicMoved")]
+    event EventHandler<DeleteEventArgs> MoveEvent;
+
+    /// <inheritdoc cref="TopicRenamed"/>
+    [Obsolete("The RenameEvent has been renamed to TopicRenamed")]
+    event EventHandler<RenameEventArgs> RenameEvent;
+
     /*==========================================================================================================================
     | GET CONTENT TYPE DESCRIPTORS
     \-------------------------------------------------------------------------------------------------------------------------*/

OnTopic/Repositories/ObservableTopicRepository.cs

@@ -65,6 +65,18 @@ public event EventHandler<TopicRenameEventArgs>? TopicRenamed {
       remove => _topicRenamed -= value;
     }
 
+    /// <inheritdoc cref="TopicDeleted"/>
+    [Obsolete("The DeleteEvent has been renamed to TopicDeleted")]
+    public event EventHandler<DeleteEventArgs>? DeleteEvent;
+
+    /// <inheritdoc cref="TopicMoved"/>
+    [Obsolete("The MoveEvent has been renamed to TopicMoved")]
+    public event EventHandler<DeleteEventArgs>? MoveEvent;
+
+    /// <inheritdoc cref="TopicRenamed"/>
+    [Obsolete("The RenameEvent has been renamed to TopicRenamed")]
+    public event EventHandler<RenameEventArgs>? RenameEvent;
+
     /*==========================================================================================================================
     | ON TOPIC LOADED
     \-------------------------------------------------------------------------------------------------------------------------*/