Optionalid?: Customer["id"]Optional pre-generated external id (cust_…). When provided it's
inserted as externalId, overriding the nanoId("cust") column default
— lets the onboarding workflow mint the id up front and reuse it as the
Temporal workflowId, which is also what makes this create idempotent.
Omit to auto-generate.
OptionalprodCustomerId?: Customer["prodCustomerId"]The prod customer a dev customer twins; omit on prod.
CustomerService.create's input.