feat: implement getRoleId method to enhance role-based access control

[yungstarry]

Description:

This pull request introduces the getRoleId method to the application. The method is designed to retrieve the ID and details of a specific role within an organization, ensuring that only authorized users can access this information. It adds an essential layer of security by verifying both the existence of the role within the specified organization and the user's permission to access the role.

Related Issue:

hngprojects/hng_boilerplate_nextjs#1445

Motivation and Context:

This change is required to enhance the security and flexibility of the application's role-based access control. By implementing this method, the system can now enforce more granular permissions, ensuring that roles are only accessible to users with the appropriate organizational context.

How Has This Been Tested?

The getRoleId method has been rigorously tested through:

• Unit Tests: Validating the correct behavior when roles exist or do not exist within the specified organization.
  

• Permission Tests: Ensuring that users without the necessary organizational association are denied access.

• Integration Tests: Checking the integration of this method with existing systems, confirming that it correctly returns role information or appropriate error messages.

• Manual Testing: Performed in a development environment to simulate real-world scenarios and edge cases.
  

Screenshots (if appropriate - Postman, etc):

Types of changes:

• New feature (non-breaking change which adds functionality)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.