Update Open Graph and Twitter image references in index.html to use raw GitHub content for improved accessibility. Add comment for future image URL switch when GitHub Pages is live.

Author: beautyfree

docs/index.html

@@ -13,9 +13,11 @@
       content="Download Skiller from GitHub — one app to sync skills across your agents."
     />
     <meta property="og:type" content="website" />
+    <!-- OG image: raw.githubusercontent.com works without GitHub Pages. After Pages is live, you can switch to:
+         https://beautyfree.github.io/skiller-skills-desktop-manager/images/og-skiller.png -->
     <meta
       property="og:image"
-      content="https://beautyfree.github.io/skiller-skills-desktop-manager/images/og-skiller.png"
+      content="https://raw.githubusercontent.com/beautyfree/skiller-skills-desktop-manager/main/docs/images/og-skiller.png"
     />
     <meta property="og:image:width" content="1200" />
     <meta property="og:image:height" content="630" />
@@ -26,7 +28,7 @@
     <meta name="twitter:card" content="summary_large_image" />
     <meta
       name="twitter:image"
-      content="https://beautyfree.github.io/skiller-skills-desktop-manager/images/og-skiller.png"
+      content="https://raw.githubusercontent.com/beautyfree/skiller-skills-desktop-manager/main/docs/images/og-skiller.png"
     />
     <title>Skiller — download</title>
     <link rel="preconnect" href="https://fonts.googleapis.com" />