Update PHP version and dependencies

[SkibidiProduction]

• Update PHP version from 8.0 to 8.4
• Add extension NumPower as dependency to composer.json
• Add numpower package to dev dependencies for using stubs
• Update PHPStan to 2.0
• Update PHPUnit to 11.0
• Fix tests to support new PHPUnit version
• Remove useless type check tests

[TheDigitalOrchard]

Would that be "minimum" dependences? PHP 8.4 is still very new. If this is a minimum, what does 8.4 offer over earlier versions that would make it mandatory?

(I selfishly ask since I'm presently unable to install PHP 8.4 due to my preferred package manager — MacPorts — not keeping up with the latest releases lately.)

[MustangZhong]

any progress on this update?