Add validation in hyoka tests for minimum Azure.Identity version detection

[KarishmaGhiya]

Reference: PR #301, Comment

Add a validation point to hyoka testing to check whether LLM-based skills correctly detect and use the required Azure.Identity package version (>= 1.16.0) when the code uses DefaultAzureCredential or DefaultAzureCredential.DefaultEnvironmentVariableName. This will help ensure errors are not introduced for developers using older versions, and that guidance is clear whenever these new features are referenced in code or documentation.

Acceptance criteria:

• Add a test (or update existing test) in hyoka that asserts the LLM suggests the proper minimum Azure.Identity version based on usage of new features in example code or skill documentation.
• Test this out with other packages as well if the appropriate version of the package gets generated when a feature is supported from a particular version
• Make sure the installation works as expected depending on your language
• Document the validation in hyoka's test plan/readme so the requirement is tracked for new or updated skills.
• Coordination with reviewers to ensure such checks are enforced for future changes affecting Azure.Identity usage.

Related context:

• Comment thread in PR #301
• .github/plugins/azure-sdk-dotnet/skills/azure-ai-agents-persistent-dotnet/SKILL.md

/cc @KarishmaGhiya @JonathanCrd