Turn Superlogical's Rex into an AI Harness

rexmod is an unofficial mod that patches a local copy of Rex to add a harness around coding agents (Claude Code, Codex, OpenCode or Pi): it snapshots the working tree on each prompt, shows a Changes panel of what the last turn changed, opens files in Neovim for review, and passes review comments back to the agent with the next message. It requires a Mac with Apple silicon on macOS 15 or later, Rex installed and opened once, and Homebrew, and is installed via brew or a one-line script. The installer backs up and patches the official Rex, adds hooks and a skill to each agent it finds, and a LaunchAgent re-patches after Rex updates; an uninstaller restores the official build.