Remove generated Tailwind CSS file and add to gitignore (#320)

This pull request removes the compiled Tailwind CSS file from version control and adds it to `.gitignore`. The generated `tailwind.css` file containing all the Tailwind utility classes, base styles, and CSS custom properties is now excluded from the repository, which is a best practice since this file should be built during the development/deployment process rather than committed to source control.

Author: gazure