Add CJ v3.1 to changelog

Author: AtibQur

sites/cheerpj/src/content/docs/22-changelog.md

@@ -2,6 +2,21 @@
 title: Changelog
 ---
 
+## [3.1](https://cheerpj.com/blog/) - February 5, 2025
+
+```html
+<script src="https://cjrtnc.leaningtech.com/3.1/cj3loader.js"></script>
+```
+
+- Maximise window support
+- Brand new "execCallback" option
+- Restore audio support
+- Various bug fixes
+- Improved font behavior
+- Improved debugging options
+- Improved performance
+
+
 ## [3.0](https://cheerpj.com/cheerpj-3-now-generally-available/) - February 1, 2024
 
 ```html