docs: private CompletableFuture<OperationResult> applyQuery(Indexed<QueryEntry> entry) {
      RaftSession session = raft.getSessions().getSession(entry.entry().session());
  
      // If the session is null then that indicates that the session already timed out or it never existed.
      // Return with an UnknownSessionException.
      if (session == null) {
        logger.warn("Unknown session: " + entry.entry().session());
        return Futures.exceptionalFuture(new RaftException.UnknownSession("unknown session " + entry.entry().session()));
      }
  
      // Execute the query using the state machine associated with the session.
      return session.getService()
          .executeQuery(
              entry.index(),
              entry.entry().sequenceNumber(),
              entry.entry().timestamp(),
              session,
              entry.entry().operation());
    }