14 chaos tests validate shard migration write safety at every cutover
boundary. Key findings:
- AE on + delta pass: 0/1M loss (production default)
- AE off + delta pass: 0/50K loss (delta pass is sufficient alone)
- AE off + delta skipped: ~2% loss → hard refusal at config validation
- 3-node cluster cutover: 0 loss with delta pass
Hard-coded policy: MigrationCoordinator refuses migrations when both
anti-entropy is disabled and delta pass is skipped. Warning logged when
AE is disabled but delta pass remains active.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
