.NET: [BREAKING] Renamed CreateAIAgent/GetAIAgent to AsAIAgent

[dmytrostruk]

Motivation and Context

Related ADR: https://github.com/microsoft/agent-framework/blob/main/docs/decisions/0011-create-get-agent-api.md

This PR renames extension methods that create local wrapper agents from CreateAIAgent/GetAIAgent to AsAIAgent, following naming conventions where As* indicates a lightweight conversion/wrapping operation without side effects.

Methods that perform server-side operations (create/retrieve agents from remote services) keep their original names.

// Before
var agent = chatClient.CreateAIAgent(options);

// After
var agent = chatClient.AsAIAgent(options);

Impacted Classes:

• Microsoft.Agents.AI
  • ChatClientExtensions - CreateAIAgent → AsAIAgent
• Microsoft.Agents.AI.OpenAI
  • OpenAIChatClientExtensions - CreateAIAgent → AsAIAgent
  • OpenAIResponseClientExtensions - CreateAIAgent → AsAIAgent
  • OpenAIAssistantClientExtensions - GetAIAgent (metadata overloads only) → AsAIAgent
• Microsoft.Agents.AI.AzureAI
  • AzureAIProjectChatClientExtensions - GetAIAgent (AgentRecord/AgentVersion overloads) → AsAIAgent
• Microsoft.Agents.AI.AzureAI.Persistent
  • PersistentAgentsClientExtensions - GetAIAgent (Response/PersistentAgent overloads) → AsAIAgent
• Microsoft.Agents.AI.Anthropic
  • AnthropicClientExtensions - CreateAIAgent → AsAIAgent
  • AnthropicBetaServiceExtensions - CreateAIAgent → AsAIAgent
• Microsoft.Agents.AI.A2A
  • A2AClientExtensions - GetAIAgent → AsAIAgent
  • A2AAgentCardExtensions - GetAIAgent → AsAIAgent

Contribution Checklist

• The code builds clean without any errors or warnings
• The PR follows the Contribution Guidelines
• All unit tests pass, and I have added new tests where possible
• Is this a breaking change? If yes, add "[BREAKING]" prefix to the title of the PR.

[Copilot]

Pull request overview

This PR implements a breaking change to rename extension methods that create local wrapper agents from CreateAIAgent/GetAIAgent to AsAIAgent, following the naming convention where As* indicates a lightweight conversion/wrapping operation without side effects. Methods that perform server-side operations (create/retrieve agents from remote services) retain their original CreateAIAgent/GetAIAgent names.

Changes:

• Renamed local wrapper methods across all agent client extension classes to use AsAIAgent naming
• Updated all test files to use the new method names
• Updated all sample files to use the new method names

Reviewed changes

Copilot reviewed 92 out of 92 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
ChatClientExtensions.cs	Renamed CreateAIAgent → AsAIAgent for local wrapper methods
ChatClientBuilderExtensions.cs	Updated calls to use AsAIAgent
OpenAIResponseClientExtensions.cs	Renamed CreateAIAgent → AsAIAgent for local wrapper methods
OpenAIChatClientExtensions.cs	Renamed CreateAIAgent → AsAIAgent for local wrapper methods
OpenAIAssistantClientExtensions.cs	Renamed GetAIAgent → AsAIAgent for metadata-based wrapper methods only
AzureAIProjectChatClientExtensions.cs	Renamed GetAIAgent → AsAIAgent for AgentRecord/AgentVersion overloads
PersistentAgentsClientExtensions.cs	Renamed GetAIAgent → AsAIAgent for Response/PersistentAgent overloads
AnthropicClientExtensions.cs	Renamed CreateAIAgent → AsAIAgent for local wrapper methods
AnthropicBetaServiceExtensions.cs	Renamed CreateAIAgent → AsAIAgent for local wrapper methods
A2AClientExtensions.cs	Renamed GetAIAgent → AsAIAgent
A2AAgentCardExtensions.cs	Renamed GetAIAgent → AsAIAgent
A2ACardResolverExtensions.cs	Updated call to use AsAIAgent
AzureAgentProvider.cs	Updated call to use AsAIAgent
Test files (13 files)	Updated all method calls from CreateAIAgent/GetAIAgent to AsAIAgent
Sample files (47 files)	Updated all method calls from CreateAIAgent/GetAIAgent to AsAIAgent

Comments suppressed due to low confidence (1)

dotnet/src/Microsoft.Agents.AI.AzureAI/AzureAIProjectChatClientExtensions.cs:199

• The XML documentation comment is misleading. The method at line 208 retrieves an existing server-side agent (as evidenced by the call to GetAgentRecordByName at line 225), it does not create a new agent. The comment should say 'Retrieves an existing server side agent' or similar to match the actual behavior and be consistent with other GetAIAgent overloads in this file.