Changelog for v3.9.0

✨ Features

• Added basic diagnostics functionality and integrated with server (3cdb422)
• Improved progress bar responsiveness for narrow screens (7804f3d)
• Updated diagnostics functionality and UI (0099116)

🐛 Bug Fixes

• None

📚 Documentation

• Updated README with diagnostics info (1826109)
• Updated screenshots and related script (3770f20)
• Updated README.md (1f19ae3, 070751c, 3ac3873, 2f1a681, 9d71dc0)

🧹 Chores & Refactoring

• Updated .env.example and deleted IMPROVEMENTS.md (3ac3873)
• Updated server index.js and public index.html (a701f03)
• Added new public JS utility and UI files (bb82610)
• Updated public HTML and existing JS files (caf6a2b)
• Updated styling and tailwind config (f605f49)
• Bumped p-limit from 4.0.0 to 6.2.0 (67175f2)
• Set release version 3.9.0 (2240f4d)