Adds hosts/desktop: 512G system disk, 1T disk for /home, each in its own
LUKS container. modules/disk.nix gains moonarch.disk.home, which moves the
/home subvolume to the second disk and drops it from the first.
New modules/user.nix declares moonarch.user without a default, so the login
name exists once per host instead of once per reference. Both hosts set an
initialPassword: swaylock authenticates through pam_unix and cannot unlock a
screen for an account without one.
nevaforget
205e3eb60f