fix thessa screenshot on home page

Author: ethmarks

layouts/index.html

@@ -49,7 +49,7 @@ <h4>ASCII-Globe</h4>
             <div class="card">
                 <a href="/posts/thessa/" class="card-link">
                     <img
-                        src="/media/thessascreenshot.webp"
+                        src="/media/thessa_2025-09-23.webp"
                         alt="A screenshot of the Thessa interface showing synonyms for the word &lsquo;screenshot&rsquo;"
                         width="1869"
                         height="964"