🔐 feat: Enhance OpenID User Info Handling

[danny-avila]

Summary

Originally #4248

• Extracted the full name retrieval logic into a separate function getFullName for better code organization and reusability
• Added environment variables OPENID_USERNAME_CLAIM and OPENID_NAME_CLAIM to customize which user info properties to use for username and name
• Added detailed documentation for the getFullName function with JSDoc comments
• Implemented extensive test coverage using MongoDB Memory Server for OpenID authentication scenarios
• Added test cases for username handling, name retrieval, and role-based access control
• Improved error handling for required role validation
• Added test cases for existing user updates and role enforcement
• Updated environment example file with new configuration options

Checklist

• My code adheres to this project's style guidelines
• I have performed a self-review of my own code
• I have commented in any complex areas of my code
• I have made pertinent documentation changes
• My changes do not introduce new warnings
• I have written tests demonstrating that my changes are effective
• Local unit tests pass with my changes