feat: Add SUPER_ADMIN role with dedicated admin user management and updated access controls for existing admin features.

src/auth/guards/roles.guard.ts

@@ -33,7 +33,11 @@ export class RolesGuard implements CanActivate {
       throw new ForbiddenException('Access denied');
     }
 
-    const hasRole = requiredRoles.some((role) => user.role === role);
+    // SUPER_ADMIN has all ADMIN privileges
+    const hasRole = requiredRoles.some((role) =>
+      user.role === role ||
+      (role === UserRole.ADMIN && user.role === UserRole.SUPER_ADMIN)
+    );
 
     if (!hasRole) {
       throw new ForbiddenException(