stampCurrent
suspend fun stampCurrent(model: AggregateModel<*>, ref: AggregateRef, cause: ObservedEvent.AccessStamped.Cause): Stamped?
Stamps the whole history of ref, of model, with the attributes of its current state, as of its last version, in its log and its other stores (target), and rewrites its snapshot; null when its log keeps no stamps or holds none of it.