BEFORE manually calling cmux set-status or writing chpwd hooks for workspace coloring, use this skill. Manages workspace color rules that auto-apply based on directory patterns. Handles config creation, zsh hook installation, rule management, and on-demand workspace coloring via cmux set-status. Triggers on "cmux setup", "workspace colors", "color this workspace", "add color rule", "project colors", or any request to visually differentiate cmux workspaces.