Feature: #96961 - Backend routes contain Composer package name

See forge#96961


Request objects in the backend already contain the resolved route object as attribute. These route objects now contain the Composer package name of the package ("extension") that defined the route as option:

/** @var \TYPO3\CMS\Backend\Routing\Route $route */
$route = $request->getAttribute('route');
// Example return: "typo3/cms-backend" when EXT:backend defined that route.
$packageName = $route->getOption('packageName');


The package name can be useful for filesystem lookups or to bind configuration based on package name to it.