Release: Prerelease 9.0.0-alpha.1

[github-actions]

This is an automated pull request that bumps the version from 9.0.0-alpha.0 to 9.0.0-alpha.1.
Once this pull request is merged, it will trigger a new release of version 9.0.0-alpha.1.
If you're not a core maintainer with permissions to release you can ignore this pull request.

To do

Before merging the PR, there are a few QA steps to go through:

• Add the "freeze" label to this PR, to ensure it doesn't get automatically forced pushed by new changes.
• Add the "ci:daily" label to this PR, to trigger the full test suite to run on this PR.

And for each change below:

1. Ensure the change is appropriate for the version bump. E.g. patch release should only contain patches, not new or de-stabilizing features. If a change is not appropriate, revert the PR.
2. Ensure the PR is labeled correctly with one of: "BREAKING CHANGE", "feature request", "bug", "maintenance", "dependencies", "documentation", "build", "unknown".
3. Ensure the PR title is correct, and follows the format "[Area]: [Summary]", e.g. "React: Fix hooks in CSF3 render functions". If it is not correct, change the title in the PR.
   • Areas include: React, Vue, Core, Docs, Controls, etc.
   • First word of summary indicates the type: “Add”, “Fix”, “Upgrade”, etc.
   • The entire title should fit on a line

This is a list of all the PRs merged and commits pushed directly to next, that will be part of this release:

• 🐛 Bug: React: Export returntype of ReactMeta#story #30580
• ❗ Breaking Change: Core: Move @storybook/instrumenter into core #30740
• ❗ Breaking Change: Typescript: Drop Typescript < 4.9 support #30736
• ✨ Feature Request: Vite: Include node_modules in stats file #30711 (will also be patched)
• ✨ Feature Request: CLI: Add index command / API #30071
• ❗ Breaking Change: Test Addon: Stabilize and remove experimental status #30727
• 🐛 Bug: Manager: Add Content-Type to prevent reliance on content type sniffing, fixing Cloud IDEs #30606 (will also be patched)
• 🐛 Bug: Vite: Improve handling of preview annotations #28798
• ✨ Feature Request: AutoBlocker: Add major version upgrade blocker #30714
• 🐛 Bug: CSF Factories: Align addon-essentials import with other addons #30716 (will also be patched)
• 🔧 Maintenance: Maintenance: Remove deprecated packages #30690
• 🐛 Bug: Next: Support Next 15.2 #30702 (will also be patched)
• 🔧 Maintenance: Revert "CLI: Don't initially select Documentation and Testing features" #30694 (will also be patched)
• 🐛 Bug: Core: Support TS3.8+ again #30700 (will also be patched)
• 🔧 Maintenance: Maintenance: Merge @storybook/core with storybook #30168
• 🐛 Bug: Codemod: Only remove types when they are unused #30644 (will also be patched)
• 📦 Dependencies: Dependencies: Upgrades #30515
• 🔧 Maintenance: CSF: Only export definePreview from the framework #30676 (will also be patched)
• 📦 Dependencies: CLI: Install prereleases of @chromatic-com/storybook #30662
• 🏗️ Build: Build: Fix check #30752
• 📝 Documentation: Docs: Add missing PRs to 8.6.0-beta.0 changelog entry #30655
• ⚠️ Direct commit: Revert "Adjust requirements for svelte-vite" 743bf903693c1a54678a85024ce5b5a2a0dac222
• ⚠️ Direct commit: Adjust requirements for svelte-vite 30f4c867c8ef474d8ef074698410d378e38d4624
• 🏗️ Build: Build: Use storybook from node_modules to run internal Storybook #30719
• 🏗️ Build: Build: Pin typescript to avoid version conflicts with eslint-typescript #30731 (will also be patched)
• 🏗️ Build: Build: Make nr build storybook work again #30721
• 📝 Documentation: Docs: Add Rsbuild Storybook builder to builders page #30693 (will also be patched)
• ⚠️ Direct commit: Revert "Svelte: Drop Support for Svelte < 5" 4cff5b53d6ef8df9e4f62c8c5d11bdb83ec01396
• ⚠️ Direct commit: Svelte: Drop Support for Svelte < 5 a4fd153de2ef19f41c101f45332081f18255d074
• 🏗️ Build: Build: Fix addon essentials entry #30696
• 🏗️ Build: Buid: Remove tailwind for now as it is failing vite postcss in experimental-nextjs-vite/default-ts #30698
• 📝 Documentation: Docs: Remove conditional content from framework pages #30669 (will also be patched)
• 🏗️ Build: Build: Remove nextjs/13-ts sandbox #30677 (will also be patched)
• 🏗️ Build: Build: Simplify and improve triggers #30683
• 📝 Documentation: Test addon: Fix incorrect link to the migration docs #30667

If you've made any changes doing the above QA (change PR titles, revert PRs), manually trigger a re-generation of this PR with this workflow and wait for it to finish. It will wipe your progress in this to do, which is expected.

Feel free to manually commit any changes necessary to this branch after you've done the last re-generation, following the Make Manual Changes section in the docs, especially if you're making changes to the changelog.

When everything above is done:

• Merge this PR
• Follow the run of the publish action

---

Generated changelog

9.0.0-alpha.1

• AutoBlocker: Add major version upgrade blocker - #30714, thanks @ndelangen!
• CLI: Add index command / API - #30071, thanks @shilman!
• CLI: Install prereleases of @chromatic-com/storybook - #30662, thanks @JReinhold!
• CSF Factories: Align addon-essentials import with other addons - #30716, thanks @kasperpeulen!
• CSF: Only export definePreview from the framework - #30676, thanks @kasperpeulen!
• Codemod: Only remove types when they are unused - #30644, thanks @yannbf!
• Core: Move @storybook/instrumenter into core - #30740, thanks @valentinpalkovic!
• Core: Support TS3.8+ again - #30700, thanks @kasperpeulen!
• Dependencies: Upgrades - #30515, thanks @ndelangen!
• Maintenance: Merge @storybook/core with storybook - #30168, thanks @ndelangen!
• Maintenance: Remove deprecated packages - #30690, thanks @ndelangen!
• Manager: Add Content-Type to prevent reliance on content type sniffing, fixing Cloud IDEs - #30606, thanks @GCHQDeveloper548!
• Next: Support Next 15.2 - #30702, thanks @kasperpeulen!
• React: Export returntype of ReactMeta#story - #30580, thanks @mrginglymus!
• Revert "CLI: Don't initially select Documentation and Testing features" - #30694, thanks @shilman!
• Test Addon: Stabilize and remove experimental status - #30727, thanks @valentinpalkovic!
• Typescript: Drop Typescript < 4.9 support - #30736, thanks @valentinpalkovic!
• Vite: Improve handling of preview annotations - #28798, thanks @tobiasdiez!
• Vite: Include node_modules in stats file - #30711, thanks @JReinhold!