message: feat(cli): clean site dir
diff: import { emptyDir } from 'fs-extra';
  -import { ES_DIR, LIB_DIR, DIST_DIR } from '../common/constant';
  +import { ES_DIR, LIB_DIR, DIST_DIR, SITE_DIST_DIR } from '../common/constant';
  export async function clean() {
  await Promise.all([
  emptyDir(ES_DIR),
  emptyDir(LIB_DIR),
  - emptyDir(DIST_DIR)
  + emptyDir(DIST_DIR),
  + emptyDir(SITE_DIST_DIR)
  ]);
  }
  