Move DO to a 3rd worker

[conico974]

BASED on #3254 and should be rebased and merged only after #3254 has been merged.

This PR moves all DO used in OpenNext to a 3rd worker.
It also introduce a fix to the incremental cache caused by multiple workers trying to write to the same key at the same time.

This also allow for preview to use DO without removing preview url.

[linear]

RND-7188 Cache put failed on cloudflare with an error around concurrent request

[changeset-bot]

⚠️ No Changeset found

Latest commit: 2fd68a2

Merging this PR will not cause a version bump for any packages. If these changes should not result in a new version, you're good to go. If these changes should result in a version bump, you need to add a changeset.

This PR includes no changesets

When changesets are added to this PR, you'll see the packages that this PR includes changesets for and the associated semver types

Click here to learn what changesets are, and how to add one.

Click here if you're a maintainer who wants to add a changeset to this PR

[github-actions]

Summary of the deployments:

Version 1

Version	URL	Status
Latest commit	https://8859011c.gitbook-open.pages.dev	✅
PR	https://pr3270.gitbook-open.pages.dev	✅

Version 2

Version	URL	Status
Vercel	https://gitbook-v2-1uu2hi5gb-gitbook.vercel.app	✅
Cloudflare	https://01048bb0-gitbook-open-v2-preview.gitbook.workers.dev	✅

Test content

Site	v1	2v	2c
GitBook	https://8859011c.gitbook-open.pages.dev/gitbook.com/docs	https://gitbook-v2-1uu2hi5gb-gitbook.vercel.app/url/gitbook.com/docs	https://01048bb0-gitbook-open-v2-preview.gitbook.workers.dev/url/gitbook.com/docs
E2E	https://8859011c.gitbook-open.pages.dev/gitbook.gitbook.io/test-gitbook-open	https://gitbook-v2-1uu2hi5gb-gitbook.vercel.app/url/gitbook.gitbook.io/test-gitbook-open	https://01048bb0-gitbook-open-v2-preview.gitbook.workers.dev/url/gitbook.gitbook.io/test-gitbook-open

[argos-ci]

The latest updates on your projects. Learn more about Argos notifications ↗︎

Build	Status	Details	Updated (UTC)
customers-v1 (Inspect)	✅ No changes detected	-	May 30, 2025, 1:45 PM
customers-v2 (Inspect)	👍 Changes approved	79 changed	May 30, 2025, 1:47 PM
default (Inspect)	✅ No changes detected	-	May 30, 2025, 1:47 PM
v2-cloudflare (Inspect)	✅ No changes detected	-	May 30, 2025, 1:49 PM
v2-vercel (Inspect)	✅ No changes detected	-	May 30, 2025, 1:50 PM

[SamyPesse]

Looks good!