launchHeadlessBrowser let puppeteer-core create and delete a temporary
Chrome profile via an unretried rm() from an eager process-exit hook. On
Windows, when an orphaned browser tree still held the profile lock, that
rm threw EBUSY and rejected the eager promise with no handler attached,
crashing OMP with an unhandled rejection during cleanup.
OMP now passes an explicit --user-data-dir, which makes puppeteer treat
the profile as non-temporary (ChromeLauncher.cleanUserDataDir becomes a
no-op), and removes the directory itself on dispose with lock-tolerant
retry, warning and leaving it in place if it stays busy rather than
crashing.
Fixes#7058
roboomp