health: fix broken pages, add image dimensions, a11y & SEO wins

Site-wide health pass (excludes in-progress blog work). Verified with a
local server + headless browser: Timeline, homepage and gallery pages load
with zero console errors and no layout distortion.

Render bugs
- Timeline page (en/mk/si): fix ../../../ paths that overshot the site root,
  so the main stylesheet and hero image load again.
- Meet Student Slovenia 2023 (en/mk/si): remove a <figure> referencing
  event3-photo-11.png, an image that was never uploaded (broken image).

Performance
- Add intrinsic width/height to 1039 raster <img> tags to prevent layout
  shift (CLS); 450 SVGs correctly skipped. Add a global
  `img { max-width:100%; height:auto }` safety net so aspect ratio is
  preserved and images never overflow.
- Preload the homepage hero (LCP) image on en/mk/si.
- Load Font Awesome non-blocking (media=print/onload swap) with a <noscript>
  fallback, on 225 pages.

Accessibility
- Add aria-label to 57 unlabeled newsletter email inputs.
- Add an sr-only <h1> to the three "My Route" pages (had no h1).
- Add an .sr-only utility class.

SEO
- Add meta descriptions to legal/msos-hub/support pages (en/mk/si).

Note: MK/SI meta descriptions are machine-drafted and should be proofread
by a native speaker before considering them final.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

en/get-to-know-slovenia/welcome-to-slovenia/index.html

@@ -56,7 +56,7 @@
     <link href="https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700&display=swap" rel="stylesheet">
     
     <!-- Font Awesome (for icons) -->
-    <link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/6.5.1/css/all.min.css" integrity="sha512-DTOQO9RWCH3ppGqcWaEA1BIZOC6xxalwEsw9c2QQeAIftl+Vegovlnee1c9QX4TctnWMn13TZye+giMm8e2LwA==" crossorigin="anonymous" referrerpolicy="no-referrer" />
+    <link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/6.5.1/css/all.min.css" integrity="sha512-DTOQO9RWCH3ppGqcWaEA1BIZOC6xxalwEsw9c2QQeAIftl+Vegovlnee1c9QX4TctnWMn13TZye+giMm8e2LwA==" crossorigin="anonymous" referrerpolicy="no-referrer" media="print" onload="this.media=&#39;all&#39;" /><noscript><link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/6.5.1/css/all.min.css" integrity="sha512-DTOQO9RWCH3ppGqcWaEA1BIZOC6xxalwEsw9c2QQeAIftl+Vegovlnee1c9QX4TctnWMn13TZye+giMm8e2LwA==" crossorigin="anonymous" referrerpolicy="no-referrer" /></noscript>
 
     <!-- Correct path to the main CSS file -->
     <link rel="stylesheet" href="../../../css/main.css">
@@ -200,7 +200,7 @@
             </header>
 
                 <figure class="article-main-image">
-                    <img fetchpriority="high" src="../../../images/slovenia-welcome-hero.webp" alt="Lake Jasna near Kranjska Gora, with mountain peaks reflected in the water">
+                    <img width="1200" height="800" fetchpriority="high" src="../../../images/slovenia-welcome-hero.webp" alt="Lake Jasna near Kranjska Gora, with mountain peaks reflected in the water">
                     <figcaption>Lake Jasna, near Kranjska Gora. Photo: Denis Sodržnik, <a href="https://travelslovenia.org/denis-sodrznik-photography/" target="_blank" rel="noopener">travelslovenia.org</a></figcaption>
                 </figure>
 
@@ -222,7 +222,7 @@
                 <p>This variety makes Slovenia easy to explore slowly. You do not need to see everything at once. The country often rewards returning to the same place in another season, with different weather and a different mood.</p>
 
                 <figure class="article-inline-image">
-                    <img loading="lazy" decoding="async" src="../../../images/slovenia-welcome-landscape.webp" alt="Vineyards and rolling hills in the Slovenian wine country">
+                    <img width="975" height="650" loading="lazy" decoding="async" src="../../../images/slovenia-welcome-landscape.webp" alt="Vineyards and rolling hills in the Slovenian wine country">
                     <figcaption>Vineyards in Bela krajina and Posavje. Photo: <a href="https://www.slovenia.info/en/things-to-do/food-and-wine/wines-of-slovenia" target="_blank" rel="noopener">slovenia.info</a></figcaption>
                 </figure>
 
@@ -237,7 +237,7 @@
                 <p>The same is true across the country. Slovenia is full of places that become meaningful because you return to them.</p>
 
                 <figure class="article-inline-image">
-                    <img loading="lazy" decoding="async" src="../../../images/slovenia-welcome-ljubljana.webp" alt="People spending time beside the Ljubljanica River in central Ljubljana">
+                    <img width="1400" height="933" loading="lazy" decoding="async" src="../../../images/slovenia-welcome-ljubljana.webp" alt="People spending time beside the Ljubljanica River in central Ljubljana">
                     <figcaption>Ljubljanica River, Ljubljana. Photo: Mankica Kranjec, Nea Culpa, <a href="https://www.slovenia.info" target="_blank" rel="noopener">slovenia.info</a></figcaption>
                 </figure>