[TASK] Split up PageLayoutView code into smaller chunks

The PageLayoutView monster class has been chunked up into smaller
parts and some other functionality was removed.

In detail this patch changes:
- start() method is removed, as it is not needed anymore
- public properties which are not in use or have been left-overs ("nextThree") are removed
- rendering a single content element is now split up into smaller parts
- rendering the "localization view" is now separated into a separate method
- unnecessary functionality in separate methods (addPageIdConstraint) is moved into the main SQL function

Resolves: #90315
Releases: master
Change-Id: I53cd10beb5904bf49618d8b9d6147701f783125f
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/63172


Tested-by: Georg Ringer <georg.ringer@gmail.com>
Tested-by: Daniel Gorges <daniel.gorges@b13.com>
Tested-by: Benni Mack <benni@typo3.org>
Reviewed-by: Georg Ringer <georg.ringer@gmail.com>
Reviewed-by: Daniel Gorges <daniel.gorges@b13.com>
Reviewed-by: Benni Mack <benni@typo3.org>