[!!!][TASK] Remove ExtDirect State Provider

The ExtDirect component for fetching the state (for the pagetree)
can be simplified by simply using the Storage.Persistent logic
which does the same.

For this, a simple inline ExtJS onReady code block is added.

All functionality related to ExtDirect State Provider is removed.

Resolves: #79227
Releases: master
Change-Id: I464ffd0608c1fd38cd81c8324f044da6f4140847
Reviewed-on: https://review.typo3.org/51224


Tested-by: TYPO3com <no-reply@typo3.com>
Reviewed-by: Wouter Wolters <typo3@wouterwolters.nl>
Reviewed-by: Oliver Hader <oliver.hader@typo3.org>
Tested-by: Oliver Hader <oliver.hader@typo3.org>
Reviewed-by: Susanne Moog <susanne.moog@typo3.org>
Tested-by: Susanne Moog <susanne.moog@typo3.org>