chore: enable tsdown devExports, move eslint to tsdown

[lachlancollins]

🎯 Changes

• devExports allows packages to export their TS source, then use the JS dist on publish.
• eslint-config was migrated to use this

✅ Checklist

• I have followed the steps in the Contributing guide.
• I have tested this code locally with pnpm test:pr.

🚀 Release Impact

• This change affects published code, and I have generated a changeset.
• This change is docs/CI/dev-only (no release).

[changeset-bot]

🦋 Changeset detected

Latest commit: d7e6675

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 2 packages

Name	Type
@tanstack/vite-config	Patch
@tanstack/eslint-config	Patch

Not sure what this means? Click here to learn what changesets are.

Click here if you're a maintainer who wants to add another changeset to this PR

[nx-cloud]

View your CI Pipeline Execution ↗ for commit d7e6675

Command	Status	Duration	Result
nx affected --targets=test:sherif,test:docs,tes...	✅ Succeeded	1s	View ↗
nx run-many --target=build	✅ Succeeded	<1s	View ↗

---

☁️ Nx Cloud last updated this comment at 2025-12-05 21:51:00 UTC

[pkg-pr-new]

npm i https://pkg.pr.new/@tanstack/eslint-config@325

npm i https://pkg.pr.new/@tanstack/publish-config@325

npm i https://pkg.pr.new/@tanstack/typedoc-config@325

npm i https://pkg.pr.new/@tanstack/vite-config@325

commit: d7e6675

[github-actions]

🎉 This PR has been released!

• @tanstack/eslint-config@0.3.4
• @tanstack/vite-config@0.4.3

Thank you for your contribution!