Added comprehensive package quantity restriction functionality that allows limiting product purchases to predefined package sizes only. Features: - Global setting to enable package quantity restrictions - Per-product override for quantity restrictions - Automatic hiding of quantity input field when restricted - Frontend validation with package selection UI - Server-side cart validation - User-friendly error messages - Complete translations for all supported languages 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>
- Add Twig template engine integration - Migrate all templates to Twig format - Add German (Switzerland, Informal) translation - Improve template organization and security - Add Composer dependency management - Create comprehensive changelog
