fix(node): prefer Module#registerHooks over Module#register (#20028)

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## Summary

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your change solve the problem?

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Fix this warning when building apps with TailwindCSS with Node 26+:
```
(node:25346) [DEP0205] DeprecationWarning: `module.register()` is deprecated. Use `module.registerHooks()` instead.
    at node:internal/util:129:11
    at Module.register (node:internal/modules/esm/loader:969:3)
    at file:///Users/antoine/Developer/my-app/node_modules/.pnpm/@tailwindcss+node@4.3.0/node_modules/@tailwindcss/node/dist/index.mjs:18:214
    at ...
```

This PR:
- Correctly prefers using `Module#registerHooks` instead of
`Module#register` by checking its availability at runtime
- Adjusts the exports of the hooks’ file by creating a synchronous
version for the new API
- Remove now unused exports from the `package.json`, relying on the
[recommended usage in the
docs](https://nodejs.org/docs/latest/api/module.html#registration-of-asynchronous-customization-hooks)
for the `Module#register` calls

## Test plan

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I'd be happy to ensure this works correctly on my end before merging
this, but it's not as trivial to test locally as a logic fix. Can you
guide me through what I need to do to test this?

I extensively based my change on the docs, following those guides:
- [Fixing imports for
`Module#register`](https://nodejs.org/docs/latest/api/module.html#registration-of-asynchronous-customization-hooks)
- [Using the new `Module#registerHooks`
function](https://nodejs.org/docs/latest/api/module.html#registration-of-synchronous-customization-hooks)

(and other more detailed sections of the same docs page)

---

Fixes #19893
Closes #19907

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Co-authored-by: Robin Malfait <malfait.robin@gmail.com>