message: plugin-api: export is*RouteRef
diff: * limitations under the License.
  */
  -export type { RouteRef, ExternalRouteRef } from './types';
  -export { createRouteRef } from './RouteRef';
  -export { createSubRouteRef } from './SubRouteRef';
  -export { createExternalRouteRef } from './ExternalRouteRef';
  +export type { RouteRef, SubRouteRef, ExternalRouteRef } from './types';
  +export { createRouteRef, isRouteRef } from './RouteRef';
  +export { createSubRouteRef, isSubRouteRef } from './SubRouteRef';
  +export { createExternalRouteRef, isExternalRouteRef } from './ExternalRouteRef';
  export { useRouteRef } from './useRouteRef';
  