Problem Description

I want to have a custom build of react, do a few experiments with, and need a repl setup with it ready to play with.

1. do this in a react repl, so we can hook it up to that
2. https://legacy.reactjs.org/docs/how-to-contribute.html#development-workflow
3. get a local build, and replace vite's react deps with the custom built one

Acceptance Criteria

• run starts react* app with no errors, using our build of react
• readme, step by step what needs to be done to rebuild it in your repo