Slack comes from the AUR and Toolbox from JetBrains' self-updating tarball,
so neither is declared: the host installs official packages only, and a
pinned archive would fight Toolbox's own updates. Slack's start and the
operator's i3 window rules become one node-display-session contribution,
because Slack's own launch-on-login is a symlink in ~/.config/autostart.
Toolbox keeps its own autostart entry as its one start. The shared
desktop.go header now names all four bundles.