fix: split type-only and runtime exports

[jeffrey-takuma]

Summary

Splits the mixed type/value re-export from @clack/core into separate type-only and runtime exports.

This avoids runtime exports such as isCancel, settings, and updateSettings being dropped by some TypeScript emitters or bundlers.

Closes #470

Testing

• pnpm build
• pnpm types

No tests were added because this only separates type-only and runtime re-exports.

[changeset-bot]

🦋 Changeset detected

Latest commit: 8310833

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

This PR includes changesets to release 1 package

Name	Type
@clack/prompts	Patch

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[pkg-pr-new]

• @example/basic

• @example/changesets

  npm i https://pkg.pr.new/@clack/core@518
  

  npm i https://pkg.pr.new/@clack/prompts@518
  

commit: 8310833

[gameroman]

Would it make sense to add a biome lint rule for this?

[43081j]

i'd rather us not have to maintain custom rules. but if this ends up existing inside biome, i'd be up for turning it on

[gameroman]

Pretty sure there is already a builtin rule for that