v1 to v2 Migration

Use this page to migrate incrementally while keeping v2 as the end state.

Route mapping

v1	v2 replacement
`GET /v1/health-check`	`GET /v2/transactions` as an authenticated smoke test
`POST /pix/v1/payment`	`POST /v2/transactions` with `method: "pix"`
`GET /pix/v1/transactions/{id}`	`GET /v2/transactions/{id}`
`POST /pix/v1/payment/refund/{id}`	`PUT /v2/transactions/{id}/refund`
`POST /pix/v1/payment/withdraw`	`POST /v2/transfers`
`POST /v1/business/integration`	modern webhook handling plus operational configuration discipline