remove unnecessary directories

As we may have update the App folder, with e.g. new Config files you would not be able to get them (if they where removed). That's why they need to be there for Composer* installation as well.

* You are installing in that way, right?

doesn't make sense at all... . Because of one future update, we need the app folder and the other directories and files?

\vendor\kint-php
\vendor\laminas

a copied to (not moved)

vendor\codeigniter4\framework\system\ThirdParty

download version ok, but not if you use a package manager.