BRREG returns addresses, vedtektsfestetFormaal, and aktivitet
as arrays of register line-fragments of one value. Element text
routinely contains commas and semicolons but never newlines, so
"\n" is the only separator that survives a round trip: a consumer
can split it back into the observed elements, which "; " and
", " do not allow. Arrays whose elements are objects
(historiskeNavn, paategninger) are repeated observations of
another unit and are nested instead: the cell is a tibble with one
row per element and one column per leaf of the element, named in
snake_case of the leaf's dot path, so the caller's column is a
list-column that tidyr::unnest() expands.