Fix me

[johnnyyliang]

Branch: backend-role-protection-fullstack

Task at Hand
Implement your code in backend/src/middleware/auth.ts, specifically the auth function.
Confirm that your code and pull request follow the Pull Request Checklist

Acceptance Criteria

All API routes in the server backend must be authentication protected. This means that only specific roles can access specific API routes. For now, implement it so that all users can retrieve information, only supervisors and above can create/edit events, and only admins can edit the FAQ page.