Build: Remove JS templates in sandboxes generation/testing

[yannbf]

Closes #

What I did

Our sandbox structure is getting quite large, so this PR proposes getting rid of the JS sandboxes as much as we can (some are left there), so all of the sandboxes that had TS/JS versions, will now only be TS.

This PR also replaces the generation and usage of CRA with a react-webpack sandbox instead, given that CRA is incredibly outdated by now.

This will decrease testing surface but I believe it won't penalize us much because of the features we test in Storybook. Also there is an upside of CI costs which will definitely go down by a lot because the sandbox count will be much lower

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

Manual testing

This section is mandatory for all contributions. If you believe no manual test is necessary, please state so explicitly. Thanks!

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

• 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.

🦋 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 canary-release-pr.yml --field pr=<PR_NUMBER>

name	before	after	diff	z	%
createSize	0 B	0 B	0 B	-	-
generateSize	77.7 MB	77.7 MB	-4.28 kB	-3.73	0%
initSize	130 MB	130 MB	14.7 kB	-1.2	0%
diffSize	52.4 MB	52.5 MB	19 kB	1.94	0%
buildSize	6.75 MB	6.75 MB	0 B	-0.65	0%
buildSbAddonsSize	1.51 MB	1.51 MB	0 B	-	0%
buildSbCommonSize	195 kB	195 kB	0 B	-	0%
buildSbManagerSize	1.86 MB	1.86 MB	0 B	1.33	0%
buildSbPreviewSize	0 B	0 B	0 B	-0.65	-
buildStaticSize	0 B	0 B	0 B	-	-
buildPrebuildSize	3.57 MB	3.57 MB	0 B	-0.65	0%
buildPreviewSize	3.19 MB	3.19 MB	0 B	0.65	0%
testBuildSize	0 B	0 B	0 B	-	-
testBuildSbAddonsSize	0 B	0 B	0 B	-	-
testBuildSbCommonSize	0 B	0 B	0 B	-	-
testBuildSbManagerSize	0 B	0 B	0 B	-	-
testBuildSbPreviewSize	0 B	0 B	0 B	-	-
testBuildStaticSize	0 B	0 B	0 B	-	-
testBuildPrebuildSize	0 B	0 B	0 B	-	-
testBuildPreviewSize	0 B	0 B	0 B	-	-

name	before	after	diff	z	%
createTime	6.8s	7.5s	709ms	-0.96	9.4%
generateTime	25.5s	20.7s	-4s -799ms	0.02	-23.2%
initTime	15.9s	14.6s	-1s -270ms	0.5	-8.6%
buildTime	8.1s	8.5s	451ms	-0.55	5.3%
testBuildTime	0ms	0ms	0ms	-	-
devPreviewResponsive	5.4s	4.4s	-974ms	-1.3	🔰-22%
devManagerResponsive	3.8s	3.2s	-588ms	-1.09	-17.9%
devManagerHeaderVisible	555ms	605ms	50ms	0.4	8.3%
devManagerIndexVisible	629ms	680ms	51ms	0.34	7.5%
devStoryVisibleUncached	1.9s	1s	-855ms	-3.23	🔰-79.5%
devStoryVisible	627ms	679ms	52ms	0.37	7.7%
devAutodocsVisible	408ms	494ms	86ms	-0.49	17.4%
devMDXVisible	562ms	519ms	-43ms	-0.04	-8.3%
buildManagerHeaderVisible	549ms	616ms	67ms	0.53	10.9%
buildManagerIndexVisible	622ms	706ms	84ms	0.7	11.9%
buildStoryVisible	498ms	569ms	71ms	0.41	12.5%
buildAutodocsVisible	440ms	516ms	76ms	1.05	14.7%
buildMDXVisible	404ms	458ms	54ms	0.49	11.8%

Greptile Summary

Here's my concise review of the changes:

Reduces CI testing surface by removing duplicate JavaScript templates in favor of TypeScript-only templates, significantly decreasing the number of sandbox tests while maintaining core functionality coverage.

• Reduced parallelism in CircleCI from 14 to 9 jobs for test-runner and e2e testing
• Removed JS templates for React, Vue, Lit, Svelte, HTML, and Preact frameworks where TS equivalents exist
• Retained essential JS-only templates like vue-cli/default-js and html-webpack/default
• Removed inDevelopment flags from stable templates to reflect production readiness
• Updated skipTasks configurations to align with new template structure

[greptile-apps]

_{2 file(s) reviewed, 1 comment(s)
Edit PR Review Bot Settings | Greptile}

[greptile-apps]

style: vue-cli/default-js is kept while other JS templates are removed - consider migrating this to TypeScript for consistency

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