Create two separate hook libraries: folder-copy, and config-manager

There are two different ways to manage PHPCS coding standards installation:

• You can copy the standards folder directly into phpcs's installed path, so they are just "there" for phpcs to use.
• You can actively manage the entries in phpcs's configuration file for the installed_paths directive, essentially informing phpcs where to find your standards in their "native" composer-installed locations.

The first method is the currently-implemented approach, but the code already exists to perform the second approach as well.

What needs to happen is this:

• Separate the two approachs out into two different classes, but that share the same public interface (making them interchangeable).
• Update the installer to check for an extra entry in the project's composer.json file that can be used as a switch to determine which method is preferred by the project (copy-folders or manage-config).
• Update the installer to use the preferred method. This should apply to both the phpcs-coding-standard type as well as the postInstall hooks.

Beginne beim Installer und untersuche den bestehenden Code zur Verwaltung von PHPCS installed_paths; prüfe anschließend, wie phpcs-coding-standard und postInstall-Hooks behandelt werden. Trenne die Ansätze copy-folders und manage-config hinter einer öffentlichen Schnittstelle, verwende den extra-Eintrag in composer.json als Umschalter und verifiziere, dass beide Installer-Pfade die ausgewählte Methode berücksichtigen.