fix: perform most operations in post-install-cmd

[youwe-petervanderwal]

Error: Composer didn't correctly recognize newly installed packages
Caused by: PackagesInstaller running in "post-package-install"
Resolved with: Running (most) installers in "post-install-cmd" instead

Resolves #60

[youwe-petervanderwal]

Note: no CHANGELOG.md -- the bug itself is caused by changes that are done in the (not yet released) 3.0.0

[Anve94]

I'm contemplating whether it makes sense to increase the verbosity of the info logs since in terms of dev experience they don't appear to add much. Currently it's showing something might happen, e.g. $event->getIO()->write('<info>Running Youwe Testing Suite pre-installer</info>');, but that doesn't really add anything outside of debugging contexts.

The installer it's actually running would be more interesting, but if it's just a 'FileInstaller' then it doesn't add much either. Since it's a major version update anyway might make sense here to increase the verbosity to require -v flag since they do read like debugging messages already anyway. Plus, seems like composer already allows passing a flag to the IO write public function write($messages, bool $newline = true, int $verbosity = self::NORMAL); to update the verbosity

In the end I'm impartial though - just something to consider - so approved.

[youwe-petervanderwal]

Regarding the verbosity @Anve94

It's a bit 'weird' if you ask me. At one point I do agree it could be a more hidden/verbose only message, on the other hand, composer outputs a lot of the operations it performs so in that sense the current implementation is in line with that...

I also kinda like that you can see why a certain file was created by the composer operation