necolas/react-native-web ? reverse-engineered prompt

I want to get this React Native for Web monorepo running cleanly on my machine and make it easy to work on. Please set it up so I can install, build, run the dev workflow, and test everything without digging through the repo.

If anything is broken or flaky, fix it and make the defaults sensible for a normal contributor. I’d also like a short, clear README update that explains how to start, build, and test the packages, and what each main task does. If you need to check the latest setup details online, do that.

After that, make sure the repo still passes the main build and test commands, and point out anything I should know before I start editing the package code.