Add npm commands to check whether node_modules is platform-independent

[fab1an]

Build systems like gradle can cache the entire npm install process and related node_modules folder and make up to date checks using the hash of the folder. Unfortunately this is packed into a zip-file which doesn't allow symlinks and it's necessary to be careful because of platform dependent modules.

I think it would help various build systems down the way if npm could provide a flag like npm --check-platform-independance that checks whether node_modules has some platform dependent code, or can be reused freely.

[kylerneva]

npm doesn’t currently provide a built-in way to check if node_modules is platform-independent. While a flag like --check-platform-independence could help build systems avoid issues with platform-specific modules, npm’s current approach relies on developers managing platform dependencies through optionalDependencies, peerDependencies, and os/cpu fields in package.json. Adding such a check would increase CLI complexity and isn’t aligned with npm’s current design philosophy.