* fix(browser): switch client-hosted profiles with staged guest replacement
Squashed from #30351 by @oliver-mee onto the current main.
Fixes#30350
* fix(browser): fence staged profile guests, release switch grants, carry host profile metadata
- A fence during automation retirement now revokes and stops the staged guest.
- A failed or late-settling switch releases its execution-host grant so the page can be recreated.
- Staging cleanup failures before handover stay visible to executor close.
- createPage/restorePage carry host-owned profile metadata to profile-switch-v1 desktops,
so recovery and restore can rebuild a switched page.
* fix(browser): roll back a switch whose replacement died, and report a lost old guest
* fix(browser): resolve client-hosted pages before the server-local target path when switching profiles
* fix(browser): a staged profile-switch guest owns downloads it starts while loading
* fix(browser): keep the original placement until a timed-out switch settles
* fix(browser): rebind the original guest before releasing a rolled-back staged guest
* test(browser): type the harness guest release mock
* fix(browser): release the replaced generation's download transfers when a switch commits
* fix(browser): admit file transfers from a staged profile-switch guest while its switch is pending
* fix(browser): release only the replaced generation's download transfers after a switch
* refactor(shared): import BrowserNetworkExecutionHost from its own module, no re-export
* fix(browser): adopt a profile switch the client finished after the caller timed out
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Co-authored-by: Oliver Mee <102673257+oliver-mee@users.noreply.github.com>
NeilandOliver Mee
Jinwoo HongandJinwoo-H