withfig/autocomplete ? reverse-engineered prompt

I want to build a macOS app that gives me IDE-style autocomplete for my terminal. It should work with shells like zsh and bash, and inside popular terminals like iTerm, Hyper, and the VS Code integrated terminal.

When I start typing a command like git, docker, or npm, a visual pop-up should appear with a searchable list of subcommands, options, and contextual arguments, complete with descriptions. It needs to feel just like the autocomplete you get in a modern code editor.

The system should be extensible, so the community can easily contribute new completion definitions for hundreds of other command-line tools. These "specs" should be written in TypeScript. Basically, I'm trying to recreate the core functionality of the old Fig app, which has since been integrated into Amazon Q.