.NET: Rename workflows projects (#975)

* Renaming Microsoft.Agent.Workflows to Microsoft.Agents.AI.Workflows

* Removing local settings.

* Removing remining old files from merge.

dotnet/src/Microsoft.Agents.AI.Workflows/WorkflowErrorEvent.cs

@@ -0,0 +1,13 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using System;
+
+namespace Microsoft.Agents.AI.Workflows;
+
+/// <summary>
+/// Event triggered when a workflow encounters an error.
+/// </summary>
+/// <param name="e">
+/// Optionally, the <see cref="Exception"/> representing the error.
+/// </param>
+public sealed class WorkflowErrorEvent(Exception? e) : WorkflowEvent(e);