Feature: #69764 - Introduced file icon detection by mime-type

See Issue #69764

Description

The IconRegistry has been extended with a mapping of file icons by mime-type. It is possible to register full mime-types main-type/sub-type but also a fallback for only the main part of the mime-type main-type/*. The core provides these fallbacks for audio/*, video/*, image/* and text/*.

Impact

It is now possible to register or overwrite the iconIdentifier for a file mime-type.

$iconRegistry = GeneralUtility::makeInstance(IconRegistry::class);
$iconRegistry->registerMimeTypeIcon('video/my-custom-type', 'icon-identifier-for-my-custom-type');