feat: Add `Hook` named export

[timfish]

import-in-the-middle has some ESM interop issues.

From here:

Specifically, namespace imports are required by the ESM spec to be objects. IITM's top-level export is not an object, but a callable function

This causes issues with some bundlers. Obviously bundled imports will not go through import-in-the-middle but using it should not inhibit bundlers as iitm can still hook build-in modules.

This PR adds a Hook named export and changes one cjs and esm test to use that new export.

[AbhiPrasad]

should we also update the README to make the named export the recommended usage?

[bengl]

@timfish should there best test additions too? I.e. if something's exported, it should be tested that that interface works?

[timfish]

should there best test additions too? I.e. if something's exported, it should be tested that that interface works?

I modified both an ESM and CJS test to use this new export!

[bengl]

I modified both an ESM and CJS test to use this new export!

Oops! I should have noticed that. 😅

And I see that other test files retain the usage of the default export. SGTM/LGTM.