Angular: Fix @angular/forms version to 21 in sandbox

[Sidnioulz]

What I did

Forced @angular/forms to stay on v21 to match other deps instead of going to v22.

Avoids this kind of CI failure.

Might need to be adjusted again in the near future once ng new starts releasing Angular 22, time will tell.

Checklist for Contributors

ø

Manual testing

• Create angular sandbox
• Go to sandbox and run build-storybook

🦋 Canary release

This PR does not have a canary release associated. You can request a canary release of this pull request by mentioning the @storybookjs/core team here.

core team members can create a canary release here or locally with gh workflow run --repo storybookjs/storybook publish.yml --field pr=<PR_NUMBER>

Summary by CodeRabbit

• Chores
  • Updated Angular CLI sandbox template dependency versioning to use a pinned version for stability.

[Copilot]

Pull request overview

Pins @angular/forms to an Angular v21 release in the Angular CLI sandbox template to prevent dependency drift (forms jumping to v22) that can break CI sandbox builds.

Changes:

• Update the Angular CLI “Latest” sandbox template to install @angular/forms@21.2.16 instead of @latest.
• Add an inline note indicating the pin should be revisited when Angular CLI starts generating Angular v22 projects by default.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[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: d9ac28ee-300f-4689-85e4-fcaf1c1cd660

📥 Commits

Reviewing files that changed from the base of the PR and between d5f75ee and 6f7b4a7.

📒 Files selected for processing (1)

• code/lib/cli-storybook/src/sandbox-templates.ts

---

📝 Walkthrough

Walkthrough

Pinned the @angular/forms dependency to version 21.2.16 in the Angular CLI sandbox template configuration, replacing the previously flexible @latest reference.

Changes

Angular Forms Version Pin

Layer / File(s)	Summary
Angular forms version pin code/lib/cli-storybook/src/sandbox-templates.ts	Updated the angular-cli/default-ts template's modifications.extraDependencies to pin @angular/forms to 21.2.16 with a comment about moving the pin later.

Estimated code review effort

🎯 1 (Trivial) | ⏱️ ~2 minutes

Possibly related PRs

• storybookjs/storybook#33955: Both PRs modify Angular v21-related version information—this PR pins @angular/forms to 21.2.16 in an Angular sandbox template, while retrieved PR updates the documented Angular supported version range to < 22.0 (covering v21).
• storybookjs/storybook#33098: Both PRs modify code/lib/cli-storybook/src/sandbox-templates.ts modifications.extraDependencies for Angular sandboxes by changing the @angular/forms version spec across different templates.
• storybookjs/storybook#33553: Both PRs modify code/lib/cli-storybook/src/sandbox-templates.ts to change the Angular CLI template's modifications.extraDependencies for @angular/forms.

✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

---

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