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/wordmark.svg

@@ -0,0 +1,11 @@
+<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 480 120" fill="none">
+  
+  <text x="0" y="74" font-family="Instrument Serif, serif" font-size="84" fill="#120f0a" letter-spacing="-3">Dave Gilligan</text>
+  <text x="2" y="100" font-family="Special Elite, monospace" font-size="13" fill="#1f5d5f" letter-spacing="5">DAVEGILLIGAN.COM</text>
+  
+  <g transform="translate(456, 60)" stroke="#8f2218" stroke-width="1.4" fill="none">
+    <path d="M 0 0 c -6 -6 -6 -14 0 -20 c 6 6 6 14 0 20 z"></path>
+    <path d="M -10 -10 c 6 -6 14 -6 20 0 c -6 6 -14 6 -20 0 z"></path>
+    <circle cx="0" cy="-10" r="2.5" fill="#8f2218"></circle>
+  </g>
+</svg>