`IntegrationsSettings/index.tsx` has carried the rule since email was extracted
on 2026-08-18: a plugin contributes panels, not settings sections. the
extraction brief said the opposite and the brief was wrong.
settings living in the platform mean this plugin is not self-contained — it
cannot be configured on an older platform, and uninstalling would leave a dead
"Atelier" section in the settings screen for someone to delete by hand.
so: a fourth panel, `atelier-providers`, and the default layout stacks it under
Collections in the right column. smallest and last because it is configured once
and then ignored — but it has to be REACHABLE, which is the whole point.
Generate's empty state pointed at "Settings → Integrations → Atelier". it now
points at the Providers panel, which is where the key actually goes.
