Add `npm cache clean --force` at the end of the base blueprint setup to prevent "idealTree already exists" errors in child blueprints. The npm global install leaves cache state that can cause issues when child blueprints run their own npm install commands. 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>