[TASK] Add support for class-string annotation and provide meta file

PhpStorm has basic support for generics since version 2021.2 which comes
in handy as since the same version the "Dynamic Return Type" plugin is broken.

Providing the class-string annotation and a proper return generic
supersedes this and recovers the built-in autocompletion.

To have the same effect for both, 3rd party code not being under our
control or methods having complex returns based on their input, a
`.phpstorm.meta.php` file is provided extending PhpStorms code awareness
capabilities.
Tons of kudos to Alexander Schnitzler providing a boilerplate
configuration here:
https://github.com/alexanderschnitzler/phpstorm.meta.php-typo3

For more information about capability extension consult
https://www.jetbrains.com/help/phpstorm/ide-advanced-metadata.html

Resolves: #95064
Releases: master, 10.4, 9.5
Change-Id: I4ea5115550ce7070de01c42c19ac3b93bf6ab4b6
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/70872


Tested-by: core-ci <typo3@b13.com>
Tested-by: Stefan Bürk <stefan@buerk.tech>
Tested-by: Andreas Fernandez <a.fernandez@scripting-base.de>
Reviewed-by: Stefan Bürk <stefan@buerk.tech>
Reviewed-by: Andreas Fernandez <a.fernandez@scripting-base.de>