Add adapters to allow SK agents to be exposed as AIAgent

[westey-m]

Motivation and Context

microsoft/agent-framework#1122

Description

Add adapters to allow SK agents to be exposed as AIAgent

Contribution Checklist

• The code builds clean without any errors or warnings
• The PR follows the SK Contribution Guidelines and the pre-submission formatting script raises no violations
• All unit tests pass, and I have added new tests where possible
• I didn't break anyone 😄

[Copilot]

Pull Request Overview

This PR adds adapters to allow Semantic Kernel (SK) agents to be exposed as AIAgent implementations from the Microsoft Agent Framework. The implementation provides a common interface conformance pattern that enables different agent types to work through the same AIAgent abstraction.

• Introduces AIAgentAdapter and AIAgentThreadAdapter classes to bridge SK agents with the Microsoft Agent Framework
• Adds extension methods for each agent type (OpenAI, Azure AI, Bedrock, etc.) to convert to AIAgent
• Creates comprehensive unit and integration tests to verify the adapter functionality

Reviewed Changes

Copilot reviewed 37 out of 37 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
dotnet/src/Agents/Abstractions/AIAgent/AIAgentAdapter.cs	Core adapter class that wraps SK agents and exposes them as AIAgent
dotnet/src/Agents/Abstractions/AIAgent/AIAgentThreadAdapter.cs	Thread adapter for bridging SK agent threads with AIAgent threads
dotnet/src/Agents/Abstractions/AgentExtensions.cs	Base extension method for converting any SK agent to AIAgent
dotnet/src/Agents/*/Extensions.cs	Agent-specific extension methods for each agent type
Unit test files	Comprehensive test coverage for all adapter functionality
Integration test files	End-to-end testing of adapter conformance

---

_{Tip: Customize your code reviews with copilot-instructions.md. Create the file or learn how to get started.}

[rogerbarreto]

Not fully sure if we need to expose the Agent, we could just recommend the GetService<Agent>() for this.

Suggested change

public Agent InnerAgent { get; }

[rogerbarreto]

The rationale here is a bit similar to where after the conversion we don't expose the converted type back as we assume the caller will have the reference already.

semantic-kernel/dotnet/src/SemanticKernel.Abstractions/AI/ChatCompletion/ChatCompletionServiceChatClient.cs

Line 18 in 3ac7861

private readonly IChatCompletionService _chatCompletionService;

Point to the GetService usage.

Suggested change

	/// <summary>
	/// Gets the underlying Semantic Kernel Agent Framework <see cref="AgentThread"/>.
	/// </summary>
	public AgentThread InnerThread { get; }

[rogerbarreto]

nit. (Internal)

For the name of this class I would do something in the same lines we did for the ChatCompletionService vs ChatClient.

i.e: SKAgentAIAgent, see ChatCompletionServiceChatClient.cs

[rogerbarreto]

This can be a strong breaking change for .Net Framework based customers as pipelines relying on GA releases will break to update a preview package.

We might need to rethink how bring this dependency...

Suggested change

	<NoWarn>$(NoWarn);NU5104</NoWarn>
	<NoWarn>$(NoWarn);</NoWarn>

[westey-m]

This error only surfaces on the package directly referencing the preview package. Anyone who references M.SK.Agents.Abstractions will not have this error for transitive references.
If this was not the case, I would have had to suppress this error for the core agents package as well, since it is also GA, and is referencing MAAI.A as a transitive reference.