mjmlio/mjml ? reverse-engineered prompt

Build me a JavaScript library for creating responsive email templates that’s easy to write and compiles into email safe HTML.

I want a simple markup language for emails, with reusable components like sections, columns, text, buttons, images, and includes, so someone can write clean template code instead of messy table HTML. It should work from Node and from a command line tool, so I can pass in a template file and get an HTML file or print the result to the terminal. It should also support watching a file or folder and rebuilding when things change.

Make sure the output is responsive, pretty well formatted by default, and can be minified if needed. Include support for basic config options like custom include paths, custom template delimiters, beautify, minify, and custom components through a config file. If anything needs current docs or edge case behavior, look it up online before coding.