Update Azure packages and refactor agent handling

[elbruno]

DETAILS

• Updated AgentLabs-01-Simple.csproj to replace the package reference for Azure.AI.Projects with Azure.AI.Agents.Persistent and updated versions of Azure.AI.Projects and Microsoft.Extensions.Configuration.UserSecrets.
• Refactored Program.cs to use PersistentAgentsClient instead of AgentsClient, including new user secrets for tenant ID and endpoint retrieval.
• Changed agent model from "gpt-4o-mini" to "gpt-4.1" and updated message handling to use asynchronous methods.
• Added agent deletion after use to clean up resources.

[github-actions]

👋 Thanks for contributing @elbruno! We will review the pull request and get back to you soon.

[Copilot]

Pull Request Overview

This PR updates Azure SDK dependencies and refactors the sample to use the new persistent agents API, modernizes the agent model, and ensures cleanup of created agents.

• Swapped out Azure.AI.Projects for Azure.AI.Agents.Persistent and bumped package versions.
• Refactored Program.cs to use PersistentAgentsClient, async message handling, and new user secrets.
• Changed model from gpt-4o-mini to gpt-4.1 and added agent deletion after use.

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
03-CoreGenerativeAITechniques/src/AgentLabs-01-Simple/Program.cs	Refactored to use PersistentAgentsClient, updated async flows, and added cleanup.
03-CoreGenerativeAITechniques/src/AgentLabs-01-Simple/AgentLabs-01-Simple.csproj	Updated package references and versions.

Comments suppressed due to low confidence (3)

03-CoreGenerativeAITechniques/src/AgentLabs-01-Simple/Program.cs:14

• [nitpick] The variable name tenantid is all lowercase and a bit ambiguous. Consider renaming to tenantId for consistency with C# naming conventions.

var tenantid = config["aifoundryproject_tenantid"];

03-CoreGenerativeAITechniques/src/AgentLabs-01-Simple/Program.cs:15

• [nitpick] The variable aifoundryproject_endpoint lacks camelCase formatting and is verbose. Consider renaming to projectEndpoint or agentEndpoint for clarity.

var aifoundryproject_endpoint = config["aifoundryproject_endpoint"];

03-CoreGenerativeAITechniques/src/AgentLabs-01-Simple/Program.cs:81

• The new agent deletion step should be covered by tests to ensure resources are cleaned up correctly in all scenarios (e.g., failures during run).

await persistentClient.Administration.DeleteAgentAsync(agentMathTutor.Id);