[#3541911] feat: UI Improvements for the Drupal Forge Browser Extension

This MR implements the proposed UI improvements from #3541911 to enhance usability and provide a more polished contributor experience.

Changes included:

• UI Enhancements

  • Refactored popup and options pages for better structure and layout.
  • Improved alignment, spacing, and overall styling using TailwindCSS v4 + DaisyUI.
  • Added "How To" modal for guidance.
  • Updated icons and labels for clarity.

• Build & Dependencies

  • Added web-ext as a dev dependency.
  • Refactored package.json scripts for clarity (build-css, build-firefox, build-chrome, build-all).

• Documentation

  • Updated README.md with clear setup instructions for Chrome, Firefox, and Safari.
  • Added Safari wrapper repo instructions (copy-paste vs. symlink).