Fix: remove duplicate author-bio includes, add author images, move inline styles

- Remove author-bio.php and article-footer.php duplicate inclusions from
  inside related article cards across 17 articles (was rendering 4x per page)
- Create /assets/images/authors/ with SVG avatars for all 7 named authors
- Move inline <style> block out of author-bio.php into main.css

includes/author-bio.php

@@ -148,110 +148,3 @@ $author_info = isset($authors[$author_name]) ? $authors[$author_name] : $authors
     </div>
 </div>
 
-<style>
-.author-bio {
-    display: flex;
-    gap: 20px;
-    padding: 24px;
-    background: linear-gradient(135deg, #f8f9fa 0%, #e9ecef 100%);
-    border-radius: 12px;
-    margin: 40px 0;
-    border-left: 4px solid #179e83;
-}
-
-.author-avatar img {
-    width: 80px;
-    height: 80px;
-    border-radius: 50%;
-    object-fit: cover;
-    border: 3px solid #179e83;
-}
-
-.author-info {
-    flex: 1;
-}
-
-.author-header {
-    font-size: 0.85rem;
-    text-transform: uppercase;
-    letter-spacing: 0.5px;
-    color: #144784;
-    margin: 0 0 8px 0;
-    font-weight: 600;
-}
-
-.author-name {
-    font-size: 1.25rem;
-    font-weight: 700;
-    color: #1a1a1a;
-    margin: 0 0 4px 0;
-}
-
-.author-role {
-    font-size: 0.95rem;
-    color: #666;
-    margin: 0 0 12px 0;
-    font-weight: 500;
-}
-
-.author-description {
-    font-size: 0.95rem;
-    color: #444;
-    line-height: 1.6;
-    margin: 0 0 16px 0;
-}
-
-.author-expertise {
-    display: flex;
-    flex-wrap: wrap;
-    gap: 8px;
-    align-items: center;
-    margin-bottom: 12px;
-}
-
-.expertise-label {
-    font-size: 0.85rem;
-    font-weight: 600;
-    color: #555;
-}
-
-.expertise-tag {
-    font-size: 0.8rem;
-    padding: 4px 10px;
-    background: #fff;
-    border: 1px solid #ddd;
-    border-radius: 16px;
-    color: #555;
-}
-
-.author-social .linkedin-link {
-    display: inline-flex;
-    align-items: center;
-    gap: 6px;
-    color: #0077b5;
-    text-decoration: none;
-    font-size: 0.9rem;
-    font-weight: 500;
-    transition: color 0.2s;
-}
-
-.author-social .linkedin-link:hover {
-    color: #005885;
-    text-decoration: underline;
-}
-
-@media (max-width: 600px) {
-    .author-bio {
-        flex-direction: column;
-        text-align: center;
-    }
-
-    .author-avatar {
-        margin: 0 auto;
-    }
-
-    .author-expertise {
-        justify-content: center;
-    }
-}
-</style>