# Issue #12: Implement Role-Based Access Control (RBAC) for Dispute Endpoints

## Description
Implement role-based access control for dispute-related endpoints to ensure that only users with the appropriate roles (`user`, `moderator`, or `admin`) can perform specific actions on disputes.

## Acceptance Criteria
- [x] Middleware `requireRole` is implemented and tested
- [x] Dispute endpoints are protected by appropriate role checks
- [x] Integration tests verify correct access control for different user roles
- [x] Documentation of RBAC in `docs/roles-and-permissions.md` is updated

## Related Files
- `backend/src/middleware/requireRole.js`
- `backend/src/middleware/requireRole.test.js`
- `backend/src/dispute-flow/`
- `docs/roles-and-permissions.md`

## Notes
This task builds upon the existing role-based access control implementation and focuses specifically on dispute-related functionality. The middleware should be used to protect endpoints in the dispute flow.