[precompile] added readme/doc files for precompile

[chrfalch]

Summary:

Added readme files for both RN dependencies and RN Core precompiled

Changelog:

[IOS] [FIXED] - Added documentation for the prebuild scripts for precompiling React Native Core and React Native Dependencies.

[react-native-bot]

	Warnings
⚠️	📋 Missing Test Plan - Can you add a Test Plan? To do so, add a "## Test Plan" section to your PR description. A Test Plan lets us know how these changes were tested.

Generated by 🚫 dangerJS against a9d30e1

[meta-codesync]

@cortinico has imported this pull request. If you are a Meta employee, you can view this in D84506769.

[cipolleschi]

Hey @chrfalch Amazing job with the docs! Thanks for working on them.

I left some comments that should improve them.

Before submitting, try to run yarn prettier as we have sevarl prettier warnings popping up!

[chrfalch]

Hey @chrfalch Amazing job with the docs! Thanks for working on them.

I left some comments that should improve them.

Before submitting, try to run yarn prettier as we have sevarl prettier warnings popping up!

Made them both simpler, also changed here and there and aligned the structure a bit better.

[cipolleschi]

Left some other suggestions for changes. There are a couple of wrong things and we need to fix the formatting, but otherwise it will be good to go.

[chrfalch]

Thanks, @cipolleschi, for the input!!

[cortinico]

/rebase

[cortinico]

@chrfalch can we make sure the CI for this one is green before I import it again?

[meta-codesync]

@cortinico merged this pull request in 7a66582.

[react-native-bot]

This pull request was successfully merged by @chrfalch in 7a66582

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