Create pr-preview.yml for Playground previews on PRs

[jeffpaul]

Description of the Change

This PR looks to make use of the WP Playground action to generate a preview button on PRs. A future iteration here would be to have a custom blueprint for ClassifAI that loads in a variety of test content that could be used for PR testing as well as on the ClassifAI Live Preview.

Copilot Summary

This pull request introduces a new GitHub Actions workflow to automate building and previewing pull requests. The workflow handles dependency installation, building the project, packaging the plugin, and providing a preview environment for PRs.

CI/CD Automation and PR Preview:

• Added a new workflow file .github/workflows/pr-preview.yml to automate building the plugin, caching dependencies, packaging the build, and exposing a preview environment for pull requests.
• Integrated steps for Node.js and PHP setup, dependency installation (via Composer and npm), and artifact caching to optimize build performance.
• Implemented artifact upload and integration with WordPress Playground for live PR previews, including blueprint generation for automated plugin installation in the preview environment.

How to test the Change

Will see what happens once I open the PR and whether a functioning Playground link appears.

Changelog Entry

Developer - Added WordPress Playground preview buttons on PRs to aid in testing new features and fixes.

Credits

Props @jeffpaul.

Checklist:

• I agree to follow this project's Code of Conduct.
• I have updated the documentation accordingly.
• I have added Critical Flows, Test Cases, and/or End-to-End Tests to cover my change.
• All new and existing tests pass.

[github-actions]

✅ WordPress Plugin Check Report

✅ Status: Passed

📊 Report

All checks passed! No errors or warnings found.

---

🤖 Generated by WordPress Plugin Check Action • Learn more about Plugin Check