.NET: Improve visibility for AzureFunctions Workflows samples run tests in increase timeouts

[westey-m]

Motivation and Context

These tests seem to be failing at the build step rather than at the run step. Separating these out to improve visibility.
Also increasing timeouts in a couple of places

Description

• Build separate from run
• Run with --no-build
• Stop waiting if the process fails
• Increase timeouts

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 improves CI failure visibility for Azure Functions workflow/sample integration tests by separating build from run and failing fast when the Functions host process exits unexpectedly.

Changes:

• Build sample projects separately before attempting to start the Functions host.
• Run Functions host with dotnet run --no-build to avoid hidden build failures during startup.
• Stop waiting for readiness if the host process exits early.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 3 comments.

File	Description
dotnet/tests/Microsoft.Agents.AI.Hosting.AzureFunctions.IntegrationTests/WorkflowSamplesValidation.cs	Adds explicit build step, runs Functions host with --no-build, and makes readiness wait fail fast on host exit.
dotnet/tests/Microsoft.Agents.AI.Hosting.AzureFunctions.IntegrationTests/SamplesValidation.cs	Updates readiness wait to fail fast if the Functions host process exits during startup.

[Copilot]

Pull request overview

Copilot reviewed 4 out of 4 changed files in this pull request and generated 4 comments.