The route dialog offers a Daybreak select (Off / On) only when the
installed model_map backend declares the `daybreak` route key and this
account's Codex catalog lists Daybreak for the chosen model (the same
capability the main model menu's Daybreak switch uses). An older plugin
that would ignore the key never gets the control.
- Switching to a model or provider without Daybreak clears the opt-in.
- A stored opt-in the plugin cannot run, or whose model is no longer
listed, stays visible with a warning so it can be turned off.
- Turning it off removes the key; the route list marks Daybreak routes.
- Strings in every locale.