gruntjs/grunt ? reverse-engineered prompt

Build me a JavaScript task runner like Grunt.

I want a command line tool that reads a project config file, lets me define named tasks, and run them from the terminal in sequence. It should support the usual stuff people expect from Grunt, like loading task files, registering custom tasks, printing useful help, and giving clear errors when something breaks.

Please make the code clean and modern, keep the existing docs and tests in mind, and make sure the main workflow actually works end to end. If there are any missing details in the docs, look up the current Grunt behavior online and match that as closely as makes sense.

I also want the repo to be easy to contribute to, so keep the structure sensible, make sure the test suite passes, and update anything obvious that would help someone install it and use it from a fresh clone.