[TASK] Fixing settings in minimal setup

Cleaning the settings and the related documentation

Lots and tons of cleanup. CodeSniffer still complains but thats mostly
because some rules are a bit wacky. With namespaces classname easily
exceed the limit of 80 characters in PHPdoc header.

Resolves: #60155
Releases: 6.2
Change-Id: Ib7bcedf95c4c2f762bcdcd1546cc6f5b936c07f0
Reviewed-on: https://review.typo3.org/31491
Reviewed-by: Sebastian Fischer
Tested-by: Sebastian Fischer