Function
Rendered once by the locale layout. It seeds in a layout effect, which runs only in the browser and only after hydration — so every reader still renders its empty server snapshot during hydration, as the progress capabilities require, and switches to the learner's data right after. A new snapshot (after a sign-in or sign-out refresh) is adopted the same way.
Renders nothing.
Hands the server's learner snapshot to the browser's learner store.