docs: update CHANGELOG.md

Author: adg-flare

CHANGELOG.md

@@ -15,6 +15,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 - `Web2Json`: removed `testApis` source, use `PublicWeb2` instead.
 - Bumped required Node.js version to 24 (lts/krypton).
+- Switched to using pnpm for package management instead of yarn.
 
 ## [1.3.1] - 2026-01-08