fix(9C): exclude database/setup.sql from the release

Caught by the build script's own SQL-dump check, which is what that
check is for.

setup.sql provisions a LOCAL database: it names `nexa_admin`, creates
two users with CHANGE_ME placeholder passwords, and documents an AMPPS
path. On cPanel the database and its users are created through cPanel,
so shipping this offers a script that names the wrong database and
either fails confusingly or succeeds and creates something nobody
wanted.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
