Variable PAYMENT_METHOD_FLOWS`Const`

PAYMENT_METHOD_FLOWS: readonly [
    "embedded",
    "redirect",
    "popup",
    "voucher_code",
    "qr_code",
] = ...

Refund state is NOT part of the payment status enum: PSPs (Stripe included) do not flip a payment's status to "refunded". Refund state is derived from amountRefunded vs amount — see getRefundState().