Deprecation: #93060 - Shortcut title must be set by controllers

See Issue #93060

Description

Previously the class ShortcutRepository automatically generated a shortcut title based on the given arguments. This generation was never reliable, especially for custom extension code, since the repository does not know about controller specific logic. Therefore, this functionality has now been marked as deprecated. Backend controllers which add a shortcut button to their module header are now required to also set the desired title.

Impact

Adding a new shortcut button without defining the $displayName triggers a PHP E_USER_DEPRECATED error.

Affected Installations

All installations using the shortcut button API without defining the $displayName property.

Migration

Define the title with TYPO3\CMS\Backend\Template\Components\Buttons\Action\ShortcutButton->setDisplayName().