Singapore Payments (HitPay — PayNow QR)

Create a payment link in SGD for Singapore via HitPay. Buyer pays with PayNow QR (the rail Singapore actually uses), cards, and other methods enabled on the HitPay account. Returns a hosted checkout URL the buyer opens to pay — payment completes automatically, no confirm step. Bring your own credentials via HTTP header (x-hitpay-api-key; free test credentials from dashboard.hit-pay.com never move real money). Money always flows buyer→HitPay→merchant; this service never touches funds.

Check whether a Singapore payment (created by create_payment_link) has been paid. Queries HitPay directly — pull-based, no webhook needed. paid=true when status is PAID.