Issue: Add Unit Tests for Role-Based Authorization Guard

[NahomAlemu]

Description

The role.guard.ts enforces role-based access control (admin, creator, user). No test coverage exists. Bugs could allow unauthorized access to restricted endpoints.

Tasks

Tasks:

• Test users with correct role can access endpoints
• Test users with wrong role are denied
• Test missing role metadata defaults to allow
• Test multiple role combinations

Visual Aids

[NahomAlemu]

Closing this as my practicum has concluded and the associated PR has been withdrawn. The branch remains available for reference.