[FEATURE] Add keyboard support for Multiselect

This patch adds keyboard support for selecting and deselecting options in
Multiselect. This should lead into a more accessible behaviour in forms
with TCA configurations like: selectMultipleSideBySide, group or folder.

Resolves: #97667
Releases: main
Change-Id: I732a3a54a7b8b8e7fd004434d1d03fb3386ecd25
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/77780


Reviewed-by: Michael Telgkamp <michael.telgkamp@mindscreen.de>
Tested-by: Georg Ringer <georg.ringer@gmail.com>
Tested-by: Michael Telgkamp <michael.telgkamp@mindscreen.de>
Tested-by: core-ci <typo3@b13.com>
Tested-by: Guido Schmechel <guido.schmechel@brandung.de>
Reviewed-by: Benni Mack <benni@typo3.org>
Reviewed-by: Georg Ringer <georg.ringer@gmail.com>
Reviewed-by: Guido Schmechel <guido.schmechel@brandung.de>
Tested-by: Benni Mack <benni@typo3.org>