[JSC] Ahead-of-time compilation - #757

No new issues found in this review. Still open from earlier code reviews: 2 findings. See the existing review comments.

This review did not follow any REVIEW.md files in this repository's folders or any CLAUDE.md files, and did not see the pull request's title or description, because it could not confirm the full list of files this pull request changes. This pull request changes so many files that the review planned its work from the changed folders, not from the full list of files, and may have looked less closely at some files. Pull requests that change fewer than 300 files avoid this.