fix: replace corepack with pnpm

[rozenmd]

Fixes #[insert GH or internal issue link(s)].

Describe your change...

---

• Reviews
  • bonk has reviewed the change
  • automated review not possible because:
• Tests
  • Tests included/updated
  • Automated tests not possible - manual testing has been completed as follows:
  • Additional testing not necessary because:

[ask-bonk]

LGTM!

Review notes

• Confirmed the review target is cloudflare/kumo PR fix: replace corepack with pnpm #795, “fix: replace corepack with pnpm”. I’ll inspect the PR diff, package metadata, lockfile changes, and existing reviews before deciding whether inline feedback is warranted.
• The checked-out commit matches the requested head SHA, and PR fix: replace corepack with pnpm #795 has no existing reviews or comments. The local clone has no origin/main ref, so I’m comparing the PR commit directly with its parent and checking the generated lockfile entries.
• The complete two-file diff is whitespace-clean. It removes the legacy packageManager pin, changes devEngines.packageManager.onFail to download, and updates the environment-lock document with the pnpm executable; this matches pnpm 12’s documented mechanism for version-managed package managers.
• The installed runner image does not include pnpm, so an install validation cannot run locally. I’m checking the repository’s dependency-install action and workflow callers to ensure they bootstrap a compatible pnpm version before relying on this manifest.
• CI bootstraps Node from .node-version through voidzero-dev/setup-vp and runs every install as vp install --frozen-lockfile; all workflow callers use this composite action. The manifest’s pnpm 12 download policy and lockfile pin are therefore applied by the supported package-manager path.
• I found no actionable regression in the changed manifest or lockfile. I’ll perform a final check of the PR’s reported workflow status; no inline review will be submitted unless that identifies a change-related failure.
• The final metadata check confirms the reviewed commit and diff are clean. CodeQL and changeset checks have passed; the package/docs workflow checks are still pending. A separate external Workers Builds: kumo-docs check is failing with no GitHub-exposed diagnostic output, so I’m inspecting its check-run metadata to determine whether it is attributable to this dependency-bootstrap change.

github run

[cloudflare-workers-and-pages]

🚀 Deploying Preview to Cloudflare 🚀

Preview URL: https://rozenmd-remove-corepack-kumo-docs.design-engineering.workers.dev (commit 5f73124)

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[pkg-pr-new]

npm i https://pkg.pr.new/@cloudflare/kumo@795

commit: 5f73124