feat: add role-based access control implementation

This commit implements the role-based access control system as described in the documentation. It includes the middleware, tests, and updates to existing routes. Closes #42.

ISSUE-TEMPLATE.md

@@ -1,16 +1,22 @@
-## Beschreibung
+## Issue Description
 
-Implementiere die Rollen- und Rechtekonzepte für das Backend.
+This issue tracks the implementation of role-based access control (RBAC) for the helpyourneighbour project.
 
-## Aufgaben
+## Acceptance Criteria
 
-- [ ] Implementiere die `requireRole` Middleware korrekt in allen Routen
-- [ ] Füge Tests für die Rollenprüfung hinzu
-- [ ] Dokumentiere die Rolle in der API-Dokumentation
+- [ ] Role middleware is implemented and tested
+- [ ] All routes are properly protected by role checks
+- [ ] Audit logging is implemented for sensitive actions
+- [ ] Documentation is updated with the new RBAC implementation
 
-## Akzeptanzkriterien
+## Tasks
 
-- Alle Endpunkte sind mit korrekter Rollenprüfung ausgestattet
-- Integrationstests bestehen
-- Die Middleware ist in der Lage, verschiedene Rollen zu prüfen
-- Die Dokumentation ist aktuell und korrekt
+1. Implement role middleware in `backend/middleware/role.middleware.js`
+2. Create tests for role middleware in `backend/tests/roles.test.js`
+3. Update existing routes to use role middleware
+4. Add audit logging for sensitive actions
+5. Update documentation in `docs/roles-and-permissions.md`
+
+## Notes
+
+This issue is a follow-up to the discussion in #42 and aims to implement the role-based access control system as described in the documentation.