Update sitemaps and improve language handling

- Updated last modification dates in static and tools sitemaps to 2026-04-01.
- Enhanced language switching in the Header component to ensure language resources are loaded before changing the language.
- Added language resource loading logic in i18n configuration to support dynamic loading of language files.
- Improved SEO route page to ensure correct language is set based on URL parameters.
- Adjusted global CSS for deferred sections to optimize rendering.
- Configured Nginx to enable Brotli compression for better performance.

frontend/index.html

@@ -30,8 +30,6 @@
     content="30+ free tools: merge, split, compress, convert PDFs, images, videos & text. No signup required." />
   <meta name="twitter:image" content="/social-preview.svg" />
   <meta name="twitter:image:alt" content="Dociva social preview" />
-  <script async src="https://pagead2.googlesyndication.com/pagead/js/adsbygoogle.js?client=ca-pub-3822257947737372"
-    crossorigin="anonymous"></script>
   <script>
     (function () {
       try {
@@ -56,13 +54,17 @@
   </script>
   <link rel="dns-prefetch" href="https://fonts.googleapis.com" />
   <link rel="dns-prefetch" href="https://fonts.gstatic.com" />
+  <link rel="dns-prefetch" href="https://www.googletagmanager.com" />
+  <link rel="dns-prefetch" href="https://www.google-analytics.com" />
+  <link rel="dns-prefetch" href="https://pagead2.googlesyndication.com" />
+  <link rel="dns-prefetch" href="https://plausible.io" />
   <link rel="preconnect" href="https://fonts.googleapis.com" />
   <link rel="preconnect" href="https://fonts.gstatic.com" crossorigin />
-  <link rel="preload" as="style"
-    href="https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700&family=Tajawal:wght@400;500;700&display=swap" />
-  <link
-    href="https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700&family=Tajawal:wght@400;500;700&display=swap"
-    rel="stylesheet" />
+  <link rel="preload" as="style" href="https://fonts.googleapis.com/css2?family=Inter:wght@400;600;700&family=Tajawal:wght@400;700&display=swap" />
+  <link rel="stylesheet" href="https://fonts.googleapis.com/css2?family=Inter:wght@400;600;700&family=Tajawal:wght@400;700&display=swap" media="print" onload="this.media='all'" />
+  <noscript>
+    <link rel="stylesheet" href="https://fonts.googleapis.com/css2?family=Inter:wght@400;600;700&family=Tajawal:wght@400;700&display=swap" />
+  </noscript>
   <title>Dociva — Free Online File Tools</title>
 </head>