Update changelog

Author: thecrypticace

CHANGELOG.md

@@ -10,6 +10,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Fixed
 
 - Allow `_` before numbers during candidate extraction ([#17961](https://github.com/tailwindlabs/tailwindcss/pull/17961))
+- Prevent duplicate suggestions when using `@theme` and `@utility` together ([#17675](https://github.com/tailwindlabs/tailwindcss/pull/17675))
 
 ## [4.1.6] - 2025-05-09