docs(studio): update React stack note

[tianma-if]

Summary

• Update the studio README tech stack note to match the current React and Zustand versions used by the package.

Validation

• git diff --check -- packages/studio/README.md

[tianma-if]

Ready for review. This PR is mergeable, kept to a small single-purpose change, and maintainer edits are enabled. Happy to adjust anything you prefer before merge.

[miguel-heygen]

Closing in the backlog value sweep. This is documentation, test-only, dependency upkeep, refactoring, or narrow diagnostic/ergonomic polish without enough current user impact or an active merge path to justify carrying it open. Please reopen or resubmit against current main if the need is still concrete.

[tianma-if]

Refreshed this documentation fix onto current main and tightened the wording to match the package contract exactly: React 19, Zustand 4/5 for consumers, with Zustand 5 used in development. Formatting and git diff --check pass; CI is rerunning.

[jrusso1020]

Thanks for the contribution! The Studio dependency documentation is now corrected in #3675, with your authorship preserved. Closing this older PR as superseded.