Include preset dependencies in main cache keys

[OskarEichler]

Summary:

Development -main builds compute the Babel preset transformer cache key from preset JavaScript sources, but omit package.json. React Native regularly updates parser and Babel plugin dependencies without changing those source files, so a dependency-only update can preserve the cache key and reuse transforms produced by an older dependency set.

Include the preset package metadata bytes in the existing MD5 input. This adds one small file read only to the memoized -main slow path; published releases remain keyed directly by their immutable package version.

Changelog:

[INTERNAL] [FIXED] - Invalidate React Native Babel preset development caches when dependency metadata changes.

Test Plan:

• Added an isolated-module regression that supplies two package metadata contents with identical preset source contents; pristine main returns the same key, while the fix returns different keys.
• Full preset Jest passes: 5/5 suites, 111/111 tests, 16 snapshots.
• Fresh Flow check reports 0 errors.
• Targeted no-ignore ESLint, Prettier, and git diff --check pass.

No transform output, public API, published-release cache behavior, or UI changes.