Changelog
modu-parking/start-payment now mirrors the current Modu Parking webapp payment flow: the webapp chooses one payment gateway and calls one /ticket/payment/.../webview/{pgType} endpoint per verified SMS session. The previous pg_types array path has been removed from the public input contract because it generated multiple upstream payment URL requests from a single ceremony and made health-check failures ambiguous.
Stop sending pg_types. Send a single pg_type value (nicepay, naverpay, or mobilians) when a specific gateway is needed; when omitted, start-payment follows the current Modu webapp default of nicepay. Shared-parking callers must pass price or total_price from check-availability. Use separate start-payment/SMS attempts when you need to validate multiple payment gateways.