[discussion] Create codemod to ease Radix Primitives migration?

## Summary

This issue is about having a codemod that people can run to migrate from Radix Primitives. The codemod would prioritize the pain points from #1239.

## Examples in other libraries

- None. I haven't seen any other libraries that have codemods to migrate from alternatives. But considering that Base UI's API is very close, and that the development on Radix Primitives has stopped a some time ago, maybe it makes sense here?

## Motivation

Save engineers' time, when we talked to developers, they seemed to want a codemod: https://www.notion.so/mui-org/2025-React-Conf-Trip-report-1d6cbfe7b66080309349c0224fb148f9?source=copy_link#285cbfe7b66080f2a854ec7b75024b35. (It's a similar idea to #601, but people don't seem to want this).