Two Gateways booting the same missing database both reach CREATE DATABASE and
only one wins; the loser aborted startup with duplicate_database (42P04) even
though the winner's catalog row was already committed and the target was
usable. Follow the SQLSTATE, like the missing-database check beside it does, so
the loser falls through to its retry. Every other failure -- permission denied
included -- still propagates untouched.
