Invoices NAV rejected outright.
OptionalresponseThe final status response, if any poll returned one.
Per-invoice results, in batch index order.
Invoices stored with warnings.
A DONE invoice can still carry WARN business messages. They do not
block the report but usually mean something is wrong with the data, so
they are surfaced separately rather than folded into accepted silently.
Invoices NAV stored successfully.