update changelog

Author: RobinMalfait

CHANGELOG.md

@@ -20,6 +20,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - _Experimental_: Add `wrap-anywhere`, `wrap-break-word`, and `wrap-normal` utilities ([#12128](https://github.com/tailwindlabs/tailwindcss/pull/12128))
 - _Experimental_: Add `@source inline(…)` ([#17147](https://github.com/tailwindlabs/tailwindcss/pull/17147))
 - Add support for literal values in `--value('…')` and `--modifier('…')` ([#17304](https://github.com/tailwindlabs/tailwindcss/pull/17304))
+- Add suggestions when `--spacing(--value(integer, number))` is used ([#17308](https://github.com/tailwindlabs/tailwindcss/pull/17308))
 
 ### [4.0.15] - 2025-03-20