feat(ui): integrate Tailwind CSS and improve dark theme support

- Add Tailwind CSS and autoprefixer dependencies to package.json and package-lock.json
- Configure PostCSS with Tailwind CSS and autoprefixer plugins
- Extend global styles with Tailwind base, components, and utilities imports
- Import custom Inter font in global styles
- Enhance dark theme toggle by setting 'data-theme' attribute on document element
- Update project version from 0.9.0 to 0.10.1

Author: EndyKaufman