fix(multiplayer): converge events through REST

server/store/outbox.go

@@ -8,8 +8,9 @@ import (
 )
 
 // OutboxEvent is the durable hand-off between a committed domain mutation and
-// transient WebSocket delivery. Consumers must make delivery idempotent by
-// event ID and only acknowledge after successful fan-out.
+// transient WebSocket publication. Consumers must make publication idempotent
+// by event ID and only acknowledge after the local adapter accepts the event.
+// Subscriber receipt is not durable; clients converge through REST recovery.
 type OutboxEvent struct {
 	EventID       string
 	AggregateType string
@@ -64,8 +65,9 @@ type OutboxDelivery func(context.Context, OutboxEvent) error
 
 // OutboxDispatcher is the durable-to-transient bridge. Read and Ack are
 // injectable so ordering can be tested without a live PostgreSQL instance.
-// Delivery is at-least-once: a crash after delivery and before acknowledgement
-// leaves the event replayable, while a delivery failure stops the batch.
+// Adapter invocation is at-least-once: a crash after invocation and before
+// acknowledgement leaves the event replayable, while an adapter failure stops
+// the batch. This does not imply that a transient subscriber received it.
 type OutboxDispatcher struct {
 	Read    func(context.Context, int) ([]OutboxEvent, error)
 	Ack     func(context.Context, string, time.Time) error