Performance: i18n Lazy Loading, Bundle-Größe halbiert

- i18n lädt EN/SR Übersetzungen nur bei Bedarf
- Hauptbundle von 356KB auf 179KB reduziert (~50%)
- Entfernt modulepreload für nicht-kritische Chunks
- Nur react-vendor und i18n-vendor werden vorgeladen

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

vite.config.ts

@@ -5,18 +5,24 @@ import mdx from '@mdx-js/rollup';
 import remarkFrontmatter from 'remark-frontmatter';
 import remarkMdxFrontmatter from 'remark-mdx-frontmatter';
 
-// Plugin to make CSS non-blocking using the print media trick
+// Plugin to make CSS non-blocking and remove unnecessary preloads
 function asyncCssPlugin(): Plugin {
   return {
     name: 'async-css',
     enforce: 'post',
     transformIndexHtml(html) {
-      // Convert blocking CSS to async loading with print media trick
-      return html.replace(
+      // Convert blocking CSS to async loading
+      html = html.replace(
         /<link rel="stylesheet" crossorigin href="(\/assets\/css\/[^"]+\.css)">/g,
         `<link rel="preload" href="$1" as="style" onload="this.onload=null;this.rel='stylesheet'">
 <noscript><link rel="stylesheet" href="$1"></noscript>`
       );
+
+      // Remove modulepreload for non-critical chunks (animations, icons loaded later)
+      html = html.replace(/<link rel="modulepreload" crossorigin href="\/assets\/js\/animations[^"]*\.js">\n?/g, '');
+      html = html.replace(/<link rel="modulepreload" crossorigin href="\/assets\/js\/icons[^"]*\.js">\n?/g, '');
+
+      return html;
     }
   };
 }