[!!!][TASK] Remove Pseudo-Site Handling

This change removes the compatibility layer of Site Handling,
called "PseudoSite" handling.

Any TypoScript-related Language properties are removed.
- config.sys_language_uid
- config.sys_language_mode
- config.sys_language_overlay
- config.locale_all
- config.language
- config.typolinkEnableLinksAcrossDomains
- typolink.useCacheHash

The hook
$GLOBALS['TYPO3_CONF_VARS']['SC_OPTIONS']['t3lib/class.t3lib_tstemplate.php']['linkData-PostProc']
is removed.

In addition, all tests related to PseudoSite and linking
without SiteHandling are removed, linking to pages without
a site will not be linked anymore.

Adding `useCacheHash` to typolink triggers a
"this does not do anything anymore" deprecation message.

Further related removals (old "pageNotFound" handling
and "useCacheHash" in all viewhelpers), are removed
separately.

Resolves: #88363
Releases: master
Change-Id: I14f2f854e69c98df7fab8b14f92f1ec2440a15a0
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/59366


Tested-by: TYPO3com <noreply@typo3.com>
Tested-by: Anja Leichsenring <aleichsenring@ab-softlab.de>
Tested-by: Andreas Fernandez <a.fernandez@scripting-base.de>
Reviewed-by: Anja Leichsenring <aleichsenring@ab-softlab.de>
Reviewed-by: Andreas Fernandez <a.fernandez@scripting-base.de>