feat: add admin guard and JWT role support

- Create AdminGuard to check user role
- Update JWT strategy to include role in payload
- Update auth service to include role in token generation
- Prepare admin module structure
- TypeScript will resolve lint errors after server restart

apps/api/dist/admin/admin-plans.service.js

@@ -0,0 +1,3 @@
+"use strict";
+Object.defineProperty(exports, "__esModule", { value: true });
+//# sourceMappingURL=admin-plans.service.js.map