README: fix broken star history chart

The star history chart in both READMEs no longer renders due to GitHub stargazer API restrictions. Switch the chart to a working mirror so the stargazer history displays again.

README.fr.md

@@ -346,7 +346,7 @@ Toutes les plateformes supportant le standard agentskills.io peuvent charger ces
 
 ## Historique des étoiles
 
-![Star History Chart](https://api.star-history.com/svg?repos=mukul975/Anthropic-Cybersecurity-Skills&type=Date)
+![Star History Chart](https://star-history.dera.page/svg?repos=mukul975/Anthropic-Cybersecurity-Skills&type=Date)
 
 ## Releases
 

README.md

@@ -363,11 +363,11 @@ All platforms that support the [agentskills.io](https://agentskills.io) standard
 
 ## Star history
 
-<a href="https://star-history.com/#mukul975/Anthropic-Cybersecurity-Skills&Date">
+<a href="https://star-history.dera.page/#mukul975/Anthropic-Cybersecurity-Skills&Date">
  <picture>
-   <source media="(prefers-color-scheme: dark)" srcset="https://api.star-history.com/svg?repos=mukul975/Anthropic-Cybersecurity-Skills&type=Date&theme=dark" />
-   <source media="(prefers-color-scheme: light)" srcset="https://api.star-history.com/svg?repos=mukul975/Anthropic-Cybersecurity-Skills&type=Date" />
-   <img alt="Star History Chart" src="https://api.star-history.com/svg?repos=mukul975/Anthropic-Cybersecurity-Skills&type=Date" width="100%" />
+   <source media="(prefers-color-scheme: dark)" srcset="https://star-history.dera.page/svg?repos=mukul975/Anthropic-Cybersecurity-Skills&type=Date&theme=dark" />
+   <source media="(prefers-color-scheme: light)" srcset="https://star-history.dera.page/svg?repos=mukul975/Anthropic-Cybersecurity-Skills&type=Date" />
+   <img alt="Star History Chart" src="https://star-history.dera.page/svg?repos=mukul975/Anthropic-Cybersecurity-Skills&type=Date" width="100%" />
  </picture>
 </a>