## Description 

This PR implements consensus folk detection by adding consensus output
digest into consensus commit prologue transaction. The digest
implementation uses the existing ConsensusOutputCommit.

## Test Plan 

Unit test to test to test basic ConsensusCommitPrologueV2
Unit test to test CheckpointSummary creates different digest if the
included ConsensusCommitPrologueV2 transactions have different consensus
output digest.

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### Type of Change (Check all that apply)

- [ ] protocol change
- [ ] user-visible impact
- [ ] breaking change for a client SDKs
- [ ] breaking change for FNs (FN binary must upgrade)
- [ ] breaking change for validators or node operators (must upgrade
binaries)
- [ ] breaking change for on-chain data layout
- [ ] necessitate either a data wipe or data migration

### Release notes