feat: add Verdaccio local npm registry for development

Adds Verdaccio service for local npm package development, allowing
packages like ai-delegate to be published and consumed locally without
going through the GitLab registry.

Usage:
1. Start Verdaccio: docker compose up -d verdaccio
2. Access web UI: http://localhost:4873
3. Publish packages: npm publish --registry http://localhost:4873

Related to #1

🤖 Generated with [Claude Code](https://claude.com/claude-code

)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>