Feature: #94452 - Improved multi-selection in file selection

See Issue #94452

Description

The file selector, which is used in TYPO3 Backend, to choose one or multiple files to be connected via sys_file_reference in the FormEngine, has been improved to have a better visual option when selecting multiple records.

Previously, there was a checkbox button at the end of each file row. The checkbox is now re-ordered and moved to the beginning of each row and is now based on our TYPO3 Icon Set.

In addition, the view is more compact and when selecting multiple items there is an option to select all items, no items or to toggle the selection. The Import selection button now has a visual text next to the icon, making it clearer what this button does.

Impact

Selection of files is now quicker to grasp for editors working with files.