gui-startup now spawns the initial window's pane against the du5t
ssh_domains entry (domain = { DomainName = "du5t" }) instead of the
default local domain, so the first pane is already connected instead
of showing a local cmd shell. The main menu still pops up on top as
before.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>