I would like to make cases like https://github.com/PHP-CS-Fixer/PHP-CS-Fixer/issues/8129 easier to debug. There is 3 things to check:

- If each respective finder behaves as expected, this is the job of the `diagnose.php`.
- Which finder result got picked: the introduce `CpuCoreFinder::trace()` should answer that.
- A way to debug `CpuCoreFinder::getAvailableForParallelisation()`. Since #127 is not released yet, the signature of `::getAvailableForParallelisation()` to return a result value object which could capture the resolved parameters to be able to figure out with which values the calculation was done.