Set up the DuskMoon UI system in the current Phoenix project. Use the skills duskmoon-dev-core, duskmoon-dev-css-art, duskmoon-elements, duskmoon_bundler, and phoenix-duskmoon-ui as needed throughout these tasks.

duskmoon_bundler is an Elixir-native frontend toolchain (Rust NIFs powered by OXC/LightningCSS/QuickBEAM) that replaces esbuild, the Tailwind CLI binary, bun, and Node.js entirely — no external binaries to download. duskmoon_npm (its transitive dependency) provides mix npm.* tasks for managing node_modules packages without a real npm/Node install.

Tasks

1. Update CLAUDE.md with UI constitution

Add or update a ## UI Library section in ./CLAUDE.md with the following constitution:

## UI Library

This project uses the DuskMoon UI system:

cmd-setup-phoenix-duskmoon

Tasks

1. Update CLAUDE.md with UI constitution