Payin intent attempt failed

Webhook event triggered when a payment attempt for a payin intent fails after authorization, but the intent survives it.

The payload carries the intent back in ready_to_pay, so the payer can retry with the same payment token while the intent lives. The failed attempt itself is reported by the payin_rejected or payin_failed webhook. When the provider rejected the payment made through the intent's dynamic QR, the QR cannot be paid again, and a payin_intent_failed with qr_code_rejected follows shortly after.