Base Processed Event
@MappedSuperclass
JPA @MappedSuperclass providing the column mapping for a row in the per-service processed_event table used by the consumer-side idempotent receiver pattern.
Concrete per-service entities extend this class with their own @Entity
@Table(name = "processed_event")annotations. The uniqueness of(event_id, consumer_group)is enforced by aUNIQUEconstraint in the Flyway migration; the constraint violation is the signal that a duplicate was received.