Introduce myHomeProfile.extraPrograms (mirrors myPackages.extra) so each
host's NixOS config declares which extra Home Manager modules it needs
on top of a shared core (fish, starship, btop, git). miku-homelab's
former home.nix becomes its extras list; vps gets home-manager for the
first time using core alone.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
