- Add createDomainEventBatcher with entity type+ID dedup within 50ms window - Domain-changed overrides all granular events in same batch - More than 10 unique entities triggers full refresh fallback - Delete action preserved during coalescing (last-write-wins otherwise) - Unknown event types trigger full refresh as safety fallback - Legacy createEventBatcher preserved for backward compatibility - Add 12 comprehensive tests for all coalescing behaviors Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>