Function alter_changes_replica_shape 

fn alter_changes_replica_shape(options: &PlanClusterOption) -> bool

Whether an ALTER statement sets a replica config shape dimension (SIZE, AVAILABILITY ZONES, either INTROSPECTION option, or EXPERIMENTAL ARRANGEMENT COMPRESSION). These dimensions use a durable reconfiguration record for MANUAL clusters. Scheduled clusters without an in-flight record take the direct realized-config path instead.

A statement-level check, used while a reconfiguration is in flight: an ALTER back to the realized shape sets a shape option without changing its value, yet must reach the reshape path to cancel the record. With nothing in flight the routing compares values instead (see sequence_alter_cluster_stage).