Update CHANGELOG for version 0.7.2 patch release

Co-authored-by: hotlong <50353452+hotlong@users.noreply.github.com>

Author: Copilot

CHANGELOG.md

@@ -19,6 +19,13 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Security
 
+## [0.7.2] - 2026-01-31
+
+### Changed
+- Updated system protocol JSON schemas (events, worker, metadata-loader)
+- Enhanced documentation structure for system protocols
+- Generated comprehensive JSON schema documentation
+
 ## [0.7.1] - 2026-01-31
 
 ### Changed
@@ -185,7 +192,8 @@ Mark breaking changes clearly:
 
 ---
 
-[Unreleased]: https://github.com/objectstack-ai/spec/compare/v0.7.1...HEAD
+[Unreleased]: https://github.com/objectstack-ai/spec/compare/v0.7.2...HEAD
+[0.7.2]: https://github.com/objectstack-ai/spec/compare/v0.7.1...v0.7.2
 [0.7.1]: https://github.com/objectstack-ai/spec/compare/v0.6.1...v0.7.1
 [0.6.1]: https://github.com/objectstack-ai/spec/compare/v0.4.1...v0.6.1
 [0.4.1]: https://github.com/objectstack-ai/spec/compare/v0.4.0...v0.4.1