Added changelog

Author: tanya732

CHANGELOG.md

@@ -1,5 +1,18 @@
 # Change Log
 
+## [v3.0.0-beta.0](https://github.com/auth0/auth0-java/tree/v3.0.0-beta.0) (2025-12-18)
+
+[Full Changelog](https://github.com/auth0/auth0-java/compare/v4.26.0...v3.0.0-beta.0)
+
+- Complete rewrite of the **Management API client** using Fern code generation
+- Update OkHttp to 5.2.1
+- API attributes can set null for patch operations
+- Nullability annotations to POJO classes
+- Fully compatible **Authentication API client** — no breaking changes
+
+- [Migration guide](v3_MIGRATION_GUIDE.md) available for upgrading from v2.x
+
+
 ## [2.26.0](https://github.com/auth0/auth0-java/tree/2.26.0) (2025-10-24)
 [Full Changelog](https://github.com/auth0/auth0-java/compare/2.25.0...2.26.0)