Orders records carry no custom fields

Context

Custom fields require an explicit entity capability decision.

Apply the recorded Commerce decision by declaring no custom fields on these records.

Opting orders into customizable fields would require Andrew to change the existing entity decision.

Order detail and composition remain purpose-built. Future configurable order data requires a new product decision.

Show evidence (sources, provenance, origins, pinned commits)

Decision: Declare no custom-field capability on Orders records and retain purpose-built administration surfaces.