Opening an already-imported Xtream portal reads the saved catalog in tens
of milliseconds, but the session made the shell mount the full-screen
import overlay right away, so it flashed for about two frames between the
skeleton and the loaded page (J2 open-source).
A session that has only read the saved catalog (loading-cached, store
isImporting still false) now shows the overlay after a 300 ms delay.
Remote import phases and refresh preparation still show it immediately,
and a slow or stuck cache read still blocks and stays cancellable.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>