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>

si/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>
 
     <!-- Povezava na glavno CSS datoteko -->
     <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>Jezero Jasna pri Kranjski Gori. Foto: Denis Sodržnik, <a href="https://travelslovenia.org/denis-sodrznik-photography/" target="_blank" rel="noopener">travelslovenia.org</a></figcaption>
                 </figure>
 
@@ -222,7 +222,7 @@
                 <p>Prav zaradi te raznolikosti je Slovenijo lepo odkrivati počasi. Ni treba videti vsega naenkrat. Pogosto se je vredno vrniti na isti kraj v drugem letnem času, ob drugačnem vremenu in v drugačnem razpoloženju.</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>Vinogradi v Beli krajini in Posavju. Foto: <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>Podobno velja tudi drugod po državi. Slovenija je polna krajev, ki postanejo pomembni zato, ker se vanje vračamo.</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, Ljubljana. Foto: Mankica Kranjec, Nea Culpa, <a href="https://www.slovenia.info" target="_blank" rel="noopener">slovenia.info</a></figcaption>
                 </figure>