feat: add custom scope when commit

[FabienBounoir]

💡 Motivation Behind This PR: Supporting Custom Commit Scopes

Currently, the scope selection is limited to a predefined list, which works well for highly structured projects. However, it can be restrictive in more flexible or open source environments, where contributors might need to define context-specific scopes.

This pull request introduces a new customScopeInput configuration option that allows:

• Keeping the current behavior with an autocomplete prompt based on predefined scopes.
• Or enabling a free-text input to let users specify custom scopes when customScopeInput: true.

🎯 Why this is valuable:

• Adds flexibility for teams and contributors who don’t have a fixed list of scopes.
• More welcoming for open-source contributors who may need custom scope definitions.
• Backward-compatible: default behavior remains unchanged.

---

✅ Summary of Changes

🛠 Feature Implementation

• [README.md]: Updated to document the new customScopeInput option.

• [lib/defaults.js]: Introduced the customScopeInput flag (default is false).

• [lib/questions/scope.js]: Updated createQuestion to:

  • Use predefined scopes + autocomplete if customScopeInput is false (default).
  • Prompt for custom input using limitedInput if customScopeInput is true.

🧪 Tests

• [test/formatCommitMessage.test.js]: Added tests with customScopeInput: false to validate current behavior and ensure proper coverage.

---

📌 Proposal

This enhancement introduces no breaking changes and brings more flexibility for users with varied workflows. It’s especially useful for open-source projects and collaborative environments.

The feature is:

• Optional and non-intrusive
• Tested
• Fully documented

I'd love to hear your feedback and am happy to make any adjustments necessary to meet your standards. Thank you for your time and consideration!