DL-378

A fabric subscriber callback returns an error (RIG-4030 option 1): func(context.Context, EventRef) error, where nil acks and an error Naks through the existing retry-then-DLQ-park path (immediate Nak, DefaultMaxDeliver = 5). The delivery consumer returns nil only for a missing message row (redelivery cannot fix it, per OQ-1) and returns every other read error, so a transient DB failure is redelivered instead of waiting up to the recovery floor tick and losing an offline recipient’s wake

Status: Active (Matt, 2026-09-27)

Record: ../../infra/runtime/compass-managed-delivery-cutover/design.md#post-freeze-amendments