docs: public boolean hasValidCredentials() {
          String accessToken = storage.retrieveString(KEY_ACCESS_TOKEN);
          String refreshToken = storage.retrieveString(KEY_REFRESH_TOKEN);
          String idToken = storage.retrieveString(KEY_ID_TOKEN);
          Long expiresAt = storage.retrieveLong(KEY_EXPIRES_AT);
  
          return !(isEmpty(accessToken) && isEmpty(idToken) ||
                  expiresAt == null ||
                  expiresAt <= getCurrentTimeInMillis() && refreshToken == null);
      }