refactor nest app to server folder

server/src/auth/roles.decorator.ts

@@ -0,0 +1,5 @@
+import { SetMetadata } from '@nestjs/common';
+import { Role } from './role.enum';
+
+export const ROLES_KEY = 'roles';
+export const Roles = (...roles: Role[]) => SetMetadata(ROLES_KEY, roles);