Per Point
@Serializable
@SerialName(value = "perPoint" )
A document-level default replication count plus per-point overrides keyed by design-point index (0-based, in the order the design enumerates them). Indices not present in overrides use default.
The index space is dynamic: it depends on which DesignSpec variant is in use and how many points it generates. Submit- time validation rejects override indices outside the enumerated range.