* [haproxy] add support for xhr-polling in real-time
* [web] try 3 WebSockets then fallback to xhr-polling when (re-)connecting
* [web] ensure old socket.io transport has been closed when reconnecting
* [web] close xhr-polling transport before leaving the page
This will de-register the client, leave the project and clean up the
connected clients tracking ASAP.
* [web] rename constant to avoid confusion
Co-authored-by: Alf Eaton <alf.eaton@overleaf.com>
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Co-authored-by: Alf Eaton <alf.eaton@overleaf.com>
GitOrigin-RevId: 55e500c341145947e5589875438fc796394b6ae4
