Address PR review comments: experimental attrs, doc fixes, token propagation

- Add [Experimental(OPENAI001)] to all 7 public Hosting types per reviewer request
- Fix McpConsentContext XML doc: 'Thread-static' -> 'Async-local' (AsyncLocal
  flows with ExecutionContext, not thread-static)
- Expand UserAgentMiddleware test regex to match prerelease versions (e.g. 1.0.0-rc.4)
- Propagate CancellationToken in AgentFrameworkResponseHandler session save

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

dotnet/src/Microsoft.Agents.AI.Foundry.Hosting/AgentFrameworkResponseHandler.cs

@@ -2,6 +2,7 @@
 
 using System;
 using System.Collections.Generic;
+using System.Diagnostics.CodeAnalysis;
 using System.Runtime.CompilerServices;
 using System.Threading;
 using Azure.AI.AgentServer.Responses;
@@ -9,6 +10,7 @@ using Azure.AI.AgentServer.Responses.Models;
 using Microsoft.Extensions.AI;
 using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.Logging;
+using Microsoft.Shared.DiagnosticIds;
 
 namespace Microsoft.Agents.AI.Foundry.Hosting;
 
@@ -17,6 +19,7 @@ namespace Microsoft.Agents.AI.Foundry.Hosting;
 /// with agent-framework <see cref="AIAgent"/> instances, enabling agent-framework agents and workflows
 /// to be hosted as Azure Foundry Hosted Agents.
 /// </summary>
+[Experimental(DiagnosticIds.Experiments.AIOpenAIResponses)]
 public class AgentFrameworkResponseHandler : ResponseHandler
 {
     private readonly IServiceProvider _serviceProvider;
@@ -275,7 +278,7 @@ public class AgentFrameworkResponseHandler : ResponseHandler
             // Persist session after streaming completes (successful or not)
             if (session is not null && !string.IsNullOrWhiteSpace(sessionConversationId))
             {
-                await sessionStore.SaveSessionAsync(agent, sessionConversationId, session, CancellationToken.None).ConfigureAwait(false);
+                await sessionStore.SaveSessionAsync(agent, sessionConversationId, session, cancellationToken).ConfigureAwait(false);
             }
         }
     }

dotnet/src/Microsoft.Agents.AI.Foundry.Hosting/AgentSessionStore.cs

@@ -1,7 +1,9 @@
 // Copyright (c) Microsoft. All rights reserved.
 
+using System.Diagnostics.CodeAnalysis;
 using System.Threading;
 using System.Threading.Tasks;
+using Microsoft.Shared.DiagnosticIds;
 
 namespace Microsoft.Agents.AI.Foundry.Hosting;
 
@@ -13,6 +15,7 @@ namespace Microsoft.Agents.AI.Foundry.Hosting;
 /// allowing conversations to be resumed across HTTP requests, application restarts,
 /// or different service instances in hosted scenarios.
 /// </remarks>
+[Experimental(DiagnosticIds.Experiments.AIOpenAIResponses)]
 public abstract class AgentSessionStore
 {
     /// <summary>

dotnet/src/Microsoft.Agents.AI.Foundry.Hosting/FoundryAIToolExtensions.cs

@@ -1,8 +1,10 @@
 // Copyright (c) Microsoft. All rights reserved.
 
 using System;
+using System.Diagnostics.CodeAnalysis;
 using Azure.AI.Projects.Agents;
 using Microsoft.Extensions.AI;
+using Microsoft.Shared.DiagnosticIds;
 
 namespace Microsoft.Agents.AI.Foundry.Hosting;
 
@@ -10,6 +12,7 @@ namespace Microsoft.Agents.AI.Foundry.Hosting;
 /// Extension methods for <see cref="FoundryAITool"/> that require Azure.AI.Projects 2.1.0-beta.1+
 /// types (e.g. <see cref="ToolboxRecord"/>, <see cref="ToolboxVersion"/>).
 /// </summary>
+[Experimental(DiagnosticIds.Experiments.AIOpenAIResponses)]
 public static class FoundryAIToolExtensions
 {
     /// <summary>

dotnet/src/Microsoft.Agents.AI.Foundry.Hosting/FoundryToolboxOptions.cs

@@ -1,12 +1,15 @@
 // Copyright (c) Microsoft. All rights reserved.
 
 using System.Collections.Generic;
+using System.Diagnostics.CodeAnalysis;
+using Microsoft.Shared.DiagnosticIds;
 
 namespace Microsoft.Agents.AI.Foundry.Hosting;
 
 /// <summary>
 /// Options for Foundry Toolbox MCP integration.
 /// </summary>
+[Experimental(DiagnosticIds.Experiments.AIOpenAIResponses)]
 public sealed class FoundryToolboxOptions
 {
     /// <summary>

dotnet/src/Microsoft.Agents.AI.Foundry.Hosting/FoundryToolboxService.cs

@@ -2,6 +2,7 @@
 
 using System;
 using System.Collections.Generic;
+using System.Diagnostics.CodeAnalysis;
 using System.Net.Http;
 using System.Threading;
 using System.Threading.Tasks;
@@ -11,6 +12,7 @@ using Microsoft.Extensions.Hosting;
 using Microsoft.Extensions.Logging;
 using Microsoft.Extensions.Logging.Abstractions;
 using Microsoft.Extensions.Options;
+using Microsoft.Shared.DiagnosticIds;
 using ModelContextProtocol.Client;
 
 namespace Microsoft.Agents.AI.Foundry.Hosting;
@@ -33,6 +35,7 @@ namespace Microsoft.Agents.AI.Foundry.Hosting;
 /// lazily connected otherwise.
 /// </para>
 /// </remarks>
+[Experimental(DiagnosticIds.Experiments.AIOpenAIResponses)]
 public sealed class FoundryToolboxService : IHostedService, IAsyncDisposable
 {
     private readonly FoundryToolboxOptions _options;

dotnet/src/Microsoft.Agents.AI.Foundry.Hosting/InMemoryAgentSessionStore.cs

@@ -1,9 +1,11 @@
 // Copyright (c) Microsoft. All rights reserved.
 
 using System.Collections.Concurrent;
+using System.Diagnostics.CodeAnalysis;
 using System.Text.Json;
 using System.Threading;
 using System.Threading.Tasks;
+using Microsoft.Shared.DiagnosticIds;
 
 namespace Microsoft.Agents.AI.Foundry.Hosting;
 
@@ -25,6 +27,7 @@ namespace Microsoft.Agents.AI.Foundry.Hosting;
 /// such as Redis, SQL Server, or Azure Cosmos DB.
 /// </para>
 /// </remarks>
+[Experimental(DiagnosticIds.Experiments.AIOpenAIResponses)]
 public sealed class InMemoryAgentSessionStore : AgentSessionStore
 {
     private readonly ConcurrentDictionary<string, JsonElement> _sessions = new();

dotnet/src/Microsoft.Agents.AI.Foundry.Hosting/McpConsentContext.cs

@@ -31,9 +31,9 @@ internal sealed class RequestConsentState
 }
 
 /// <summary>
-/// Thread-static (AsyncLocal) context that enables <see cref="ConsentAwareMcpClientAIFunction"/>
+/// Async-local context that enables <see cref="ConsentAwareMcpClientAIFunction"/>
 /// to signal a consent error back to <see cref="AgentFrameworkResponseHandler"/> through the
-/// <see cref="FunctionInvokingChatClient"/> tool loop.
+/// <see cref="FunctionInvokingChatClient"/> tool loop. Flows with the async ExecutionContext.
 /// </summary>
 internal static class McpConsentContext
 {

dotnet/src/Microsoft.Agents.AI.Foundry.Hosting/ServiceCollectionExtensions.cs

@@ -1,6 +1,7 @@
 // Copyright (c) Microsoft. All rights reserved.
 
 using System;
+using System.Diagnostics.CodeAnalysis;
 using System.Reflection;
 using System.Threading.Tasks;
 using Azure.AI.AgentServer.Responses;
@@ -11,6 +12,7 @@ using Microsoft.AspNetCore.Http;
 using Microsoft.AspNetCore.Routing;
 using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.DependencyInjection.Extensions;
+using Microsoft.Shared.DiagnosticIds;
 
 namespace Microsoft.Agents.AI.Foundry.Hosting;
 
@@ -18,6 +20,7 @@ namespace Microsoft.Agents.AI.Foundry.Hosting;
 /// Extension methods for registering agent-framework agents as Foundry Hosted Agents
 /// using the Azure AI Responses Server SDK.
 /// </summary>
+[Experimental(DiagnosticIds.Experiments.AIOpenAIResponses)]
 public static class FoundryHostingExtensions
 {
     /// <summary>

dotnet/tests/Microsoft.Agents.AI.Foundry.UnitTests/Hosting/UserAgentMiddlewareTests.cs

@@ -20,7 +20,7 @@ namespace Microsoft.Agents.AI.Foundry.UnitTests.Hosting;
 /// </summary>
 public sealed partial class UserAgentMiddlewareTests : IAsyncDisposable
 {
-    private const string VersionedUserAgentPattern = @"agent-framework-dotnet/\d+\.\d+\.\d+";
+    private const string VersionedUserAgentPattern = @"agent-framework-dotnet/\d+\.\d+\.\d+(-[\w.]+)?";
 
     private WebApplication? _app;
     private HttpClient? _httpClient;