Add user settings endpoint

[MaryammAli]

• Description: Add API for updating learner and tutor preferences.
  • Path: BackendAcademy/src/users/

[ekwe7]

I would love to work on this issue. I have experience building production ready applications and collaborating through GitHub workflows. I'll carefully analyze the current implementation, propose a reliable solution, and submit a well-tested PR. My focus is on clean code, maintainability, and timely delivery