Authenticated subscription disclosure via batch authorization omission

Incorrect authorization in Ash Framework AshGraphql before 1.11.0 allows remote authenticated users to receive restricted subscription payloads. AshGraphql.Subscription.Batcher.do_send/5 applies should_send?/1 only to the first notification, then publishes later batch results without suppressing forbidden or not-found errors. Exploitation requires authorized subscriptions and at least two qualifying notifications in one batch; disclosure is limited to record existence, timing, and identifiers carried in errors.