🚀 Feature Request: Import the unenv preset for cloudflare

[vicb]

We want to import the unenv preset from cloudflare in this monorepo as @cloudflare/unenv-preset

@pi0 has extracted the preset from unenv to https://github.com/pi0/unenv-preset-cloudflare 🙏

TODO:

• import https://github.com/pi0/unenv-preset-cloudflare
• Sync with latest unenv
• Add peerDependencies on workerd and unenv
• Enable testing the dev version
• Setup the npm release for @cloudflare/unenv-preset
• Wrangler should update workerd when it is pushed to prod
• Wrangler should depend on the npm release of @cloudflare/unenv-preset
  • update deps.ts to include @cloudflare/unenv-preset.
• workerd update PR should update @cloudflare/unenv-preset (automatically via the peerDep)
• rename $cloudflare.ts to index.ts, see import unenv-preset  #7370 (comment)
• createEnv, see import unenv-preset  #7370 (comment)

/cc @petebacondarwin

[pi0]

As tests are non-blockers and dependent to unenv repo structure, I think we can keep it in unenv repo in meanwhile and potentially use @cloudflare/unenv-preset as an external preset until move is done.