fix: Cloudflare adapter integrations

[teemingc]

This PR fixes a few issues as a follow up to #851

1. The referenced types file needs to be a relative path. Otherwise, TS thinks it's a package name and you get an error in the tsconfig.json file such as:

Cannot find type definition file for 'worker-configuration.d.ts'.
  The file is in the program because:
    Entry point of type library 'worker-configuration.d.ts' specified in compilerOptions

2. The preview port needs to be 4173 so that it works with the Playwright command which targets the same port. Otherwise, wrangler dev defaults to port 8080 and the Playwright test:e2e script fails

[changeset-bot]

🦋 Changeset detected

Latest commit: 271ea16

The changes in this PR will be included in the next version bump.

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commit: 387cac1

[jycouet]

Other than small changeset tweaks, LGTM

[manuel3108]

Thanks!