chore: import upstream snapshot with attribution

dotnet/tests/Microsoft.Agents.AI.Workflows.UnitTests/Futures/FuturesScope.cs

@@ -0,0 +1,27 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using System;
+
+namespace Microsoft.Agents.AI.Workflows.UnitTests.Futures;
+
+/// <summary>
+/// Sets <see cref="Workflows.Futures.EnableAgentResponseOutputTaggingAndFiltering"/> for
+/// the lifetime of the scope, restoring the prior value on dispose. Pair every use with
+/// <c>using</c> and run inside the <c>FuturesSerial</c> xUnit collection to avoid leaking
+/// state across parallel tests.
+/// </summary>
+internal sealed class FuturesScope : IDisposable
+{
+    private readonly bool _previous;
+
+    public FuturesScope(bool enabled)
+    {
+        this._previous = Workflows.Futures.EnableAgentResponseOutputTaggingAndFiltering;
+        Workflows.Futures.EnableAgentResponseOutputTaggingAndFiltering = enabled;
+    }
+
+    public void Dispose()
+    {
+        Workflows.Futures.EnableAgentResponseOutputTaggingAndFiltering = this._previous;
+    }
+}