stamp
open suspend override fun stamp(ref: AggregateRef, access: Map<String, Any?>, asOf: Int, from: Int, until: Int): Int
One update_by_query of the documents of ref of the versions from from until until, each guarded in the query and in its script: a document is written when it has no ElasticsearchEventIndex.ACCESS_VERSION, one before asOf, or asOf with other attributes (a new model's). A document another stamp changed meanwhile is a version conflict, passed over and searched again, so the later of two stamps wins whatever their order.