feat: migrate Payload CMS to MDX and harden static infrastructure

components/Header.tsx

@@ -168,6 +168,7 @@ export default function Header() {
                 alt={t('home')}
                 width={120}
                 height={120}
+                sizes="(max-width: 768px) 120px, 120px"
                 style={{ width: 'auto' }}
                 className="h-10 md:h-14 w-auto transition-all duration-500 group-hover:scale-110"
                 priority
@@ -463,7 +464,14 @@ export default function Header() {
             )}
             style={{ transitionDelay: isMobileMenuOpen ? '800ms' : '0ms' }}
           >
-            <Image src="/logo-white.svg" alt={t('home')} width={80} height={80} unoptimized />
+            <Image
+              src="/logo-white.svg"
+              alt={t('home')}
+              width={80}
+              height={80}
+              sizes="80px"
+              unoptimized
+            />
           </div>
         </nav>
       </div>