Writes what a listing needs from the answers of the app's "first
listing" form: the dataset in the data catalog (added when missing), the
report (a Listing, added when missing), its listings row (the company's
listing type; the order: the group, the subject, the start date when the
data have one) and one listing_cols row per column, in order, headed by
the data's label (a repeated group or subject printed once).