Create CONTRIBUTING.md

[tarmojussila]

This pull request adds a new CONTRIBUTING.md file to the repository, providing clear guidelines for contributors. The documentation covers project structure, development setup, instructions for making changes, submitting pull requests, and release management.

Contributor documentation:

• Added a comprehensive CONTRIBUTING.md file outlining how to contribute, including project structure, development setup, change process, pull request guidelines, release workflow, and licensing.

[github-actions]

Z.ai Code Review

Here is the review of the CONTRIBUTING.md addition:

Logic & Process Issues

1. Potential .gitignore Conflict:
   The documentation emphasizes that dist/ must be committed. However, standard Node.js .gitignore templates often exclude the dist/ directory by default.

   • Action: Add a specific instruction telling contributors to check .gitignore and ensure dist/ is not ignored, otherwise, they will struggle to commit the required files.

2. Build Drift Risk:
   The instructions rely on developers manually running npm run build before every commit. It is very common for developers to update src/index.js but forget to rebuild, resulting in a PR where src/ and dist/ are out of sync.

   • Action: Consider adding a CI workflow check (or a recommended pre-commit hook) that verifies dist/index.js is up-to-date with the source code. This ensures the action actually runs the code defined in the PR.

Consistency & Configuration

3. Verify action.yml Configuration:
   • Action: Double-check that the runs.main field in the existing action.yml file explicitly points to dist/index.js.
   • Action: Ensure the runs.node-version (if specified) in action.yml aligns with the "Node.js 20+" prerequisite stated in this document.