OptionalmessageOptionalpayOptional caller-supplied "tap to pay" link for the recipient SMS. Shortened via the short-URL service and embedded as the CTA. Not persisted on the request row — it only feeds the create-time notification.
Customer-scoped identity id of the requester.
Requester's E.164 phone — shown to the recipient; the self-send guard
compares it against recipientPhone.
Human-decimal amount (e.g. 1.31), per the financial-services BigNumber convention. Persisted as the decimal value.