[Feature] Add log message when validator halts due to quorum failure.

[kyle-u410]

🚀 Feature

When chain cannot advance because of a lack of validators or bonded stake participating. All the remaining validators should emit a clear failure log indicating reason of chain halt.

Would be even better is halt is due to newly added validator then the log message would report inactive validators or recently added validators.

Motivation

This would help clearly indicate if chain halts are consensus state related or some issue with the VM and transaction processing.