feat(azure-ai-projects): add endpoint evaluator samples for API Key auth and entra id auth

[ahmad-nader]

Add two E2E samples demonstrating endpoint-based evaluators:

• sample_endpoint_evaluator_with_api_key.py: API Key authentication flow
• sample_endpoint_evaluator_with_entra_id.py: Entra ID (managed identity) authentication flow

Both samples show the full workflow: create connection, register evaluator, create evaluation, run with inline data, and poll for results.

Description

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• The pull request does not introduce [breaking changes]
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[github-actions]

Thank you for your contribution @ahmad-nader! We will review the pull request and get back to you soon.

[Copilot]

Pull request overview

This PR adds two end-to-end sample scripts to azure-ai-projects demonstrating endpoint-based evaluators — one using API Key authentication and one using Entra ID (managed identity). Each sample walks through creating a workspace connection, registering an evaluator, creating an evaluation, running it with inline data, and polling for results. The samples are intended to live alongside the existing evaluation samples under samples/evaluations/.

The main blocking concern is that both samples depend on a model (EndpointBasedEvaluatorDefinition) that does not exist in the package on the PR's base branch (main), so neither sample can import or run as-is. There is also a Black-formatting issue in the API Key sample, and the new samples are not added to the evaluations README.md index (which the repo convention maintains, though that file is outside this PR's diff).

Changes:

• Adds sample_endpoint_evaluator_with_entra_id.py (managed-identity auth flow via a CustomKeys/AAD connection).
• Adds sample_endpoint_evaluator_with_api_key.py (API key auth flow via an ApiKey connection, with an EvaluatorMetric definition).
• Both rely on EndpointBasedEvaluatorDefinition, which is not present in the SDK.

Reviewed changes

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

File	Description
sdk/ai/azure-ai-projects/samples/evaluations/sample_endpoint_evaluator_with_entra_id.py	New Entra ID auth endpoint-evaluator sample; imports nonexistent EndpointBasedEvaluatorDefinition.
sdk/ai/azure-ai-projects/samples/evaluations/sample_endpoint_evaluator_with_api_key.py	New API Key auth endpoint-evaluator sample; imports nonexistent EndpointBasedEvaluatorDefinition and has a mis-indented metrics block that fails Black.