docs: update changelog

CHANGELOG.md

@@ -4,7 +4,11 @@ All notable changes to this project will be documented in this file.
 
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/), and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
-## Unreleased
+## [Unreleased]
+
+Nothing yet.
+
+## [0.4.0] - 2024-12-09
 
 ### Added
 
@@ -34,3 +38,6 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/),
 ### Removed
 
 - `types.ts` file removed.
+
+[unreleased]: https://github.com/nekonyx/next-auth-steam/compare/v0.4.0...HEAD
+[0.4.0]: https://github.com/nekonyx/next-auth-steam/releases/tag/v0.4.0