[TASK] Localize preview boxes

* Make the box shown when previewing in Frontend either a hidden page or
  an unpublished version in a workspace use translated labels
* Add missing htmlspecialchars() calls
* Restore the link to stop the preview
* Use translation of LanguageService to use the language of the current
  backend user

Resolves: #83352
Releases: master
Change-Id: I4a00965d02e549f4953d0a9b891e2469a7ff9a64
Reviewed-on: https://review.typo3.org/55108


Tested-by: TYPO3com <no-reply@typo3.com>
Reviewed-by: Mathias Schreiber <mathias.schreiber@typo3.com>
Tested-by: Mathias Schreiber <mathias.schreiber@typo3.com>
Reviewed-by: Benni Mack <benni@typo3.org>
Tested-by: Benni Mack <benni@typo3.org>