Initialize a nix shell environment with Claude Code in a target project directory. ## Usage ``` /init-nix-shell ~/src/myproject ``` ## Instructions 1. Ask for the absolute path to the destination directory. Resolve relative paths. 2. Validate the destination exists (offer to `mkdir -p` if not). 3. If `shell.nix` or `.envrc` already exist in the destination, warn and confirm before overwriting. 4. Copy both files from `/Users/ngpestelos/src/dotfiles/nix-template/` to the destination. 5. Confirm what was copied, then print next steps: ``` Next steps: 1. cd <destination> 2. direnv allow (if using direnv) 3. nix-shell (Claude Code installs automatically on first activation) 4. Run 'claude' ```