💳 Create Payment Link

Sent as X-API-Key header

btq-service base URL (without /payment-invoices)

return_url — customer is redirected here after payment (optional)

callback_url — webhook with the payment status

International format (E.164), e.g. +905321112233

user_id — must be a UUID. Auto-generated if empty.

click_id — auto-generated if empty

Address details (optional)