feat: update site URLs and enhance image handling

- Changed site URLs in docker-compose and deployment configurations to remove "www" prefix for consistency.
- Improved image handling by introducing warmPostCardImages function for pre-fetching images in posts and tags.
- Enhanced PostCard component with responsive image sizes for better performance.
- Updated layout to include robots meta tag and JSON-LD structured data for improved SEO.
- Added loading state for images in TopBanner component to enhance user experience.

src/app.css

@@ -1,11 +1,11 @@
-/* Windwiderstand Design System – Fonts */
+/* Windwiderstand Design System – Fonts
+   Nur erlaubte Gewichte (02-typography.md: 300/400/500/600/700). 800/900 entfernt.
+   @fontsource setzt font-display: swap als Default — Text sichtbar während Font-Load. */
 @import "@fontsource/inter/latin-300.css";
 @import "@fontsource/inter/latin-400.css";
 @import "@fontsource/inter/latin-500.css";
 @import "@fontsource/inter/latin-600.css";
 @import "@fontsource/inter/latin-700.css";
-@import "@fontsource/inter/latin-800.css";
-@import "@fontsource/inter/latin-900.css";
 @import "@fontsource-variable/lora";
 
 @import "tailwindcss";
@@ -334,6 +334,10 @@ main ol li {
   @apply mt-4 mb-3;
 }
 
+.markdown hr {
+  @apply border-stein-200 border-dotted mb-4;
+}
+
 .markdown li,
 .markdown li p {
   @apply mt-0 mb-0;