fix(errors): align three error names with their documented reference

[SurefireStudios]

Changes

• Three entries in errors-data.ts carry a name that doesn't match their export: MissingLocale → MissingLocaleError, MissingIndexForInternationalization → MissingIndexForInternationalizationError, NoManifestAvailable → NoManifestAvailableError. The other 129 all match.

• The error reference pages are published under the unsuffixed names, and the dev overlay prints err.name (overlay.ts, this.text('#name', err.name)). So a user hits the error, sees MissingLocaleError, and can't find it:

  slug	status
  /en/reference/errors/missing-locale/	200
  /en/reference/errors/missing-locale-error/	404

  Same for the other two. The page for missing-locale never contains the string MissingLocaleError, so searching the docs for what the overlay showed finds nothing. That's the case the README's "users should always be able to find an error by searching" rule is there to prevent.

• Changed name to match the export in those three, plus a changeset.

Happy to flip this the other way if you'd rather keep the names and rename the exports — that would move the doc slugs to missing-locale-error etc. and break the existing URLs, which is why I went this direction, but it's your call.

Testing

packages/astro/test/units/manifest/ambient.test.ts asserted error.name === 'NoManifestAvailableError'; updated to the new value. That's the only reference to any of the three strings in the repo.

I couldn't run the unit suite locally — it imports from dist/, and building needs the internal astro-scripts toolchain that my filtered install skipped, so I'm relying on CI for that. Biome is clean on both changed files.

Docs

The reference pages are generated from this file, so they already show the unsuffixed names — this makes the runtime agree with them. No docs change needed as far as I can tell, but flagging in case you read it differently. /cc @withastro/maintainers-docs

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[changeset-bot]

🦋 Changeset detected

Latest commit: 391d377

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

This PR includes changesets to release 1 package

Name	Type
astro	Patch

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[codspeed]

Merging this PR will not alter performance

✅ 21 untouched benchmarks

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_{Comparing SurefireStudios:fix/error-names-match-docs (391d377) with main (cf5d72f)¹}

Footnotes

1. No successful run was found on main (db2eaf1) during the generation of this report, so cf5d72f was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩