* Don't use the system 'postgres' database by default
* Use postgres adapter defaults
The pgx code actually goes to great lengths to make postgres connections
Just Work(tm) out of the box, including supporting `~/.pg_service.conf`,
SSL certificates, UNIX sockets if it can find a socket at a common path,
and falling back to TCP to localhost if not.
(On Windows, it won't try to use UNIX sockets, but will read credentials
from %appdata% as is standard over there.)
By applying our flags as overrides only when they're specified, database
connections should Just Work(tm) anywhere `psql gotosocial` does.