Function create_consistency_requirement 

pub fn create_consistency_requirement(
    layout: &BackupLayoutGuard,
    plan: &OperationPlanRecord,
    record: &ConsistencyRequirementRecord,
) -> Result<(), ConsistencyPersistenceError>

Durably create fixed consistency-requirement.json without replacing original evidence.

Requires the exact original plan already retained under layout exclusion. This persists the reviewed guarantee, not an active fence, paid allowance or release permit.

Errors

Rejects mismatched/missing original plan, excessive bytes, unsafe/existing paths and IO/locks.