docs: add v1.5.2 unreleased section to CHANGELOG

Author: tanhtm

CHANGELOG.md

@@ -5,6 +5,14 @@ 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]
+
+### Changed
+
+- Migrate all hardcoded `neutral-*` and `sky-*` color classes to DaisyUI semantic tokens (`base-content`, `primary`, `secondary-content`, `base-100/200/300`) for theme-aware styling with proper dark mode support
+- Add `styles.css` stylesheet and `scripts/tailwind.sh` build script for Tailwind CSS compilation pipeline
+- Configure hatch build to include `styles.css` and documentation files in sdist distribution
+
 ## [1.5.1] - 2026-05-11
 
 ### Fixed