feat: Add license management and tabbed settings (v0.3.0)

- Implement license management using magdev/wc-licensed-product-client
- Reorganize settings page into License, Default Settings, Integrations tabs
- Add license validation and activation via AJAX
- Frontend features require valid license (admin works always)
- Update translations with German (de_CH) for license strings

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

CHANGELOG.md

@@ -7,6 +7,28 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+## [0.3.0] - 2026-01-29
+
+### Added
+
+- License management integration using `magdev/wc-licensed-product-client` package
+- Tabbed settings page with License, Default Settings, and Integrations tabs
+- License validation and activation via AJAX with real-time status updates
+- License status banner showing current license state and expiration
+- License checks for frontend components (unlicensed sites show message instead of content)
+
+### Changed
+
+- Reorganized settings page into three tabs for better organization
+- Frontend features (player, shortcodes, ActivityPub) now require valid license
+- Admin/backend functionality works regardless of license status
+
+### Security
+
+- Server secret stored securely in WordPress options
+- HMAC signature verification for license server responses
+- Nonce verification for all license AJAX operations
+
 ## [0.2.0] - 2026-01-28
 
 ### Added