Implement version 0.0.1 - Licensed Product type for WooCommerce

Add complete plugin infrastructure for selling software with license keys:

- New "Licensed Product" WooCommerce product type
- License key generation (XXXX-XXXX-XXXX-XXXX format) on order completion
- Domain-based license validation system
- REST API endpoints (validate, status, activate, deactivate)
- Customer My Account "Licenses" page
- Admin license management under WooCommerce > Licenses
- Checkout domain field for licensed products
- Custom database tables for licenses and product versions
- Twig template engine integration
- Full i18n support with German (de_CH) translation

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

CHANGELOG.md

@@ -0,0 +1,48 @@
+# Changelog
+
+All notable changes to this project will be documented in this file.
+
+The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
+and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
+
+## [Unreleased]
+
+## [0.0.1] - 2024-01-21
+
+### Added
+
+- Initial plugin structure with WordPress Plugin API integration
+- New WooCommerce product type "Licensed Product" for selling software licenses
+- License key generation with format XXXX-XXXX-XXXX-XXXX on order completion
+- Domain-based license validation (licenses bound to specific domains)
+- REST API endpoints for license management:
+  - `POST /wp-json/wc-licensed-product/v1/validate` - Validate license for domain
+  - `POST /wp-json/wc-licensed-product/v1/status` - Check license status
+  - `POST /wp-json/wc-licensed-product/v1/activate` - Activate license on domain
+  - `POST /wp-json/wc-licensed-product/v1/deactivate` - Deactivate license
+- Checkout domain field for licensed products
+- Customer account page "Licenses" to view purchased licenses
+- Admin interface for license management (WooCommerce > Licenses)
+- License settings per product:
+  - Maximum activations per license
+  - License validity period (days or lifetime)
+  - Optional binding to major software version
+  - Current version tracking
+- Custom database tables for licenses and product versions
+- Twig template engine integration for views
+- Full internationalization support (i18n)
+- German (Switzerland, formal) translation (de_CH)
+- WooCommerce HPOS compatibility
+- Responsive frontend license table
+
+### Technical
+
+- PHP 8.3+ required
+- WooCommerce 10.0+ required
+- PSR-4 autoloading via Composer
+- Twig 3.0 template engine
+- WordPress REST API integration
+- Custom WooCommerce product type extending WC_Product
+
+[Unreleased]: https://src.bundespruefstelle.ch/magdev/wc-licensed-product/compare/v0.0.1...HEAD
+[0.0.1]: https://src.bundespruefstelle.ch/magdev/wc-licensed-product/releases/tag/v0.0.1