controller_buckaroo_redirect
Handle Buckaroo checkout callbacks.
Handle Buckaroo's POST return at /buckaroo/ready/:payment_nr. Verify the
returned signature before updating a known transaction's local status. Redirect
the visitor to payment_psp_done even when signature verification fails; an invalid
signature does not authorize a status change.
Generate the endpoint through its dispatch rule, for example:
{% url buckaroo_payment_redirect payment_nr=payment_nr %}
This provider-facing endpoint uses the verification described above rather than an administrator login.