docs: add star history chart to README

Author: madkoding

README.md

@@ -168,3 +168,6 @@ MIT - Ver [LICENSE](LICENSE) para detalles.
 
 <!-- AUTO-UPDATE-DATE -->
 **Última actualización:** 2026-02-26 15:51:02 -03
+## Star History
+
+[![Star History Chart](https://api.star-history.com/svg?repos=madkoding/git-reports&type=Date)](https://star-history.com/#madkoding/git-reports&Date)