Add complete Open Graph metadata layer across all 20 pages

- Add og:title, og:description, og:image, og:url, og:type, og:site_name to BaseLayout
- Add og:locale (en_GB) + og:locale:alternate (fr_FR, nb_NO) multilingual signals
- Add article:published_time, article:section, article:author on all 5 article pages
- Add Twitter/X summary_large_image card and canonical link on every page
- Generate 13 Jazz Noir branded 1200x630 PNG OG images (satori + resvg-js)
- Add scripts/generate-og-images.mjs + Special Elite font for future regeneration
- Add public/images/articles/ and public/assets/ which were previously untracked

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

public/assets/schools/jagiellonian.svg

@@ -0,0 +1,9 @@
+<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 480 280">
+  <rect width="480" height="280" rx="28" fill="#7a1718"></rect>
+  <rect x="24" y="24" width="432" height="232" rx="22" fill="none" stroke="#d8bb74" stroke-width="2"></rect>
+  <text x="240" y="96" fill="#f1d08d" font-family="Georgia, serif" font-size="28" letter-spacing="5" text-anchor="middle">UNIWERSYTET</text>
+  <text x="240" y="146" fill="#ffffff" font-family="Georgia, serif" font-size="42" font-weight="700" text-anchor="middle">JAGIELLONIAN</text>
+  <line x1="122" y1="164" x2="358" y2="164" stroke="#d8bb74" stroke-width="1.5"></line>
+  <text x="240" y="198" fill="#f1d08d" font-family="Arial, sans-serif" font-size="17" letter-spacing="5" text-anchor="middle">EST. 1364</text>
+  <text x="240" y="224" fill="#dcb0a8" font-family="Arial, sans-serif" font-size="14" letter-spacing="4" text-anchor="middle">KRAKOW</text>
+</svg>