feat: add PHPStan error identifiers

[owenvoke]

This PR adds error identifiers to allow ignoring errors in the new // @phpstan-ignore comment format. I'm assuming larastanStrictRules is ok as a base identifier, but happy to change this if you want to prefix it with canvural or similar.

This allows for something like:

Cache::forget('abc'); // @phpstan-ignore larastanStrictRules.noFacadeRule

I've also fixed some uses of the NunoMaduro\Larastan namespace, which should now be Larastan\Larastan. 👍🏻