Surface code snippets for undefined steps

[davidjgoss]

🤔 What's changed?

Add support for code snippets (suggestions) for undefined steps.

This manifests in two ways:

• In the suggestion messages - CCK samples that include these are now passing
• In the node test output, via what we pass to the UndefinedError - these get syntax highlighted too, so they stand out and are more readable in the terminal

The code will either be plain JavaScript or, if we detect at least some user-authored code came from ts files, TypeScript.

⚡️ What's your motivation?

Fixes #36.

🏷️ What kind of change is this?

• ⚡ New feature (non-breaking change which adds new behaviour)

📋 Checklist:

• I agree to respect and uphold the Cucumber Community Code of Conduct
• I've changed the behaviour of the code
  • I have added/updated tests to cover my changes.
• My change requires a change to the documentation.
  • I have updated the documentation accordingly.
• Users should know about my change
  • I have added an entry to the "Unreleased" section of the CHANGELOG, linking to this pull request.

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[davidjgoss]

See DefinitelyTyped/DefinitelyTyped#74159