The client's Settings > T5DE chooses the hub from the next start on (POST /hub/server, kept in server.json);
without a choice, -channel (which the client passes) decides: staging for nightly and dev, T5DE's hub for
releases. $T5DE_HUB still wins. Each hub's sign-in, product IDs and products are kept in their own folder
(T5DE's hub in the data folder as before, others in hubs/<host>), so a hub never gets another's token and
product IDs from two hubs never clash; a sign-in saved for another hub is ignored. Signing in always goes to
this run's hub.
Co-Authored-By: Claude Opus 5.5 <[email protected]>
