Build: Run yarn dedupe after sandbox install

[ndelangen]

Closes #

What I did

react-latest--vite---typescript---vitest went red on next after #35790 kept the published before-storybook lockfile. The failing log shows nested React under @storybook/addon-docs (Invalid hook call), not act-environment warnings.

This PR tries the least invasive fix: after every sandbox’s final yarn install, run yarn dedupe so Yarn can collapse nested copies before vitest/e2e/etc.

No new resolutions entries. Applies to all sandboxes, not only React.

If CI still fails, we can fall back to pinning react / react-dom resolutions (as nextjs sandboxes already do).

Checklist for Contributors

Testing

The changes in this PR are covered in the following automated tests:

• stories
• unit tests
• integration tests
• end-to-end tests

Covered by sandbox vitest jobs under ci:daily / ci:merged, especially react-latest--vite---typescript---vitest.

Manual testing

1. yarn task sandbox --template react-vite/default-ts --no-link --debug
2. In the sandbox: find node_modules -path '*/react/package.json' | sort
3. Prefer a single React (no nest under @storybook/addon-docs)
4. yarn task vitest-integration --template react-vite/default-ts --no-link -s vitest-integration

Documentation

• Add or update documentation reflecting your changes
• If you are deprecating/removing a feature, make sure to update
  MIGRATION.MD

Checklist for Maintainers

• When this PR is ready for testing, make sure to add ci:normal, ci:merged or ci:daily GH label to it to run a specific set of sandboxes. The particular set of sandboxes can be found in code/lib/cli-storybook/src/sandbox-templates.ts

• Declare whether manual QA will be needed for this PR during the next release, through qa:needed or qa:skip

• Make sure this PR contains one of the labels below:

  Available labels

  • bug: Internal changes that fixes incorrect behavior.
  • maintenance: User-facing maintenance tasks.
  • dependencies: Upgrading (sometimes downgrading) dependencies.
  • build: Internal-facing build tooling & test updates. Will not show up in release changelog.
  • cleanup: Minor cleanup style change. Will not show up in release changelog.
  • documentation: Documentation only changes. Will not show up in release changelog.
  • feature request: Introducing a new feature.
  • BREAKING CHANGE: Changes that break compatibility in some way with current major version.
  • other: Changes that don't fit in the above categories.

[storybook-app-bot]

Package Benchmarks

^{Commit: dd06496, ran on 7 August 2026 at 12:21:34 UTC}

No significant changes detected, all good. 👏

[ndelangen]

Research follow-up

The earlier act-compat diagnosis was wrong for this CI failure. CircleCI job 1858884 shows nested React under @storybook/addon-docs and zero act(async) without await warnings.

The branch has been force-pushed to the resolutions fix instead. #34708 / act-compat remains a separate issue if we still want that fix later.

[ndelangen]

Updated: dropped the resolutions approach. The PR now only runs yarn dedupe after the final install for every sandbox. Report back from CI whether that collapses the nested React under @storybook/addon-docs.

[Copilot]

Copilot was unable to review this pull request because the user who requested the review has reached their quota limit.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro

Run ID: c5d8cda9-934e-4efd-846a-2d7a4f980885

📥 Commits

Reviewing files that changed from the base of the PR and between 700765b and dd06496.

📒 Files selected for processing (1)

• scripts/tasks/sandbox.ts

---

Walkthrough

The sandbox task now runs yarn dedupe after dependency installation and before migrations. The command uses sandbox context, dry-run/debug options, and explicit progress and error messages.

Changes

Sandbox dependency flow

Layer / File(s)	Summary
Deduplicate sandbox dependencies scripts/tasks/sandbox.ts	The task imports exec and runs yarn dedupe in the sandbox after reinstalling dependencies and before migrations. It passes dry-run/debug options and reports progress or failure.

Possibly related PRs

• storybookjs/storybook#35790: This PR also changes sandbox Yarn installation and lockfile management around the new deduplication step.

✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

---

_{Comment @coderabbitai help to get the list of available commands.}