fix(*): Apply fixes reported before ship week

[dimkl]

Description

Update @clerk/nextjs error messages to refer to clerkMiddleware() and deprecated authMiddleware() and fix a typo in cannotRenderSignUpComponentWhenSessionExists error message.
There was also some internal refactoring for parseError helper.

Checklist

• npm test runs as expected.
• npm run build runs as expected.
• (If applicable) JSDoc comments have been added or updated for any package exports
• (If applicable) Documentation has been updated

Type of change

• 🐛 Bug fix
• 🌟 New feature
• 🔨 Breaking change
• 📖 Refactoring / dependency upgrade / documentation
• other:

Packages affected

• @clerk/backend
• @clerk/chrome-extension
• @clerk/clerk-js
• @clerk/clerk-expo
• @clerk/fastify
• gatsby-plugin-clerk
• @clerk/localizations
• @clerk/nextjs
• @clerk/clerk-react
• @clerk/remix
• @clerk/clerk-sdk-node
• @clerk/shared
• @clerk/themes
• @clerk/types
• build/tooling/chore

[changeset-bot]

🦋 Changeset detected

Latest commit: 7f12fff

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

This PR includes changesets to release 10 packages

Name	Type
@clerk/clerk-js	Patch
@clerk/backend	Patch
@clerk/nextjs	Patch
@clerk/chrome-extension	Patch
@clerk/clerk-expo	Patch
@clerk/fastify	Patch
gatsby-plugin-clerk	Patch
@clerk/remix	Patch
@clerk/clerk-sdk-node	Patch
@clerk/elements	Patch

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[royanger]

Errors look good.