Invoices - Generate payment method

Generates a PIX QR Code or Boleto for paying a specific invoice. The payment method is generated on demand and has an expiration time.

PIX: Returns a QR Code (string, base64 image, and copy-paste code) for instant payment. Boleto: Returns barcode, digitable line, and a PDF download URL.

The amount includes any applicable fines and interest (if overdue) or discounts (if early payment).

Partial payment: Optionally pass installment_ids to pay only specific installments instead of the full invoice. When provided, the generated payment method will cover only the selected installments. If omitted, the payment covers the entire invoice balance.