liveness

Liveness guarantees that the system will continue processing transactions even if some nodes fail.活性保证即使某些节点发生故障，系统也将继续处理交易。

A rollup with strong liveness ensures users can always withdraw funds regardless of sequencer behaviour or downtime.具有强大活性的 rollup 可确保用户无论排序器行为如何或发生停机，始终可以提取资金。