feat(nextjs,backend,types): adds accountless signup to nextjs app router (opt in only for now)

[davidlumley]

Description

Before, users needed to sign up to Clerk to copy and paste environment keys before they got started building. This is a bit of friction when you're trying to focus on learning a new framework or building your business logic.

This feature attempts to eliminate this requirement when ran in development mode.

It does this by first trying to load ephemeral keys from a local cache. If these keys do not exist, it fetches them from Clerk's API and stores them locally before using them for any future Clerk requests.

To enable this, the environment variable CLERK_FEATURE_FLAG_EPHEMERAL_ACCOUNTS must be set to true.

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:

[changeset-bot]

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Latest commit: 48d904e

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