vault/ui/app/serializers/metrics/config.js

import ApplicationSerializer from '../application';

export default ApplicationSerializer.extend({
  normalizeResponse(store, primaryModelClass, payload, id, requestType) {
    const normalizedPayload = {
      id: payload.id,
      data: {
        ...payload.data,
        enabled: payload.data.enabled.includes('enabled') ? 'On' : 'Off',
      },
    };
    return this._super(store, primaryModelClass, normalizedPayload, id, requestType);
  },
});