feat(hero): add AI-generated 'From Code to Production' architecture banner to homepage

src/pages/index.astro

@@ -60,6 +60,21 @@ const featuredMetrics: Record<string, string> = {
     <p class="hero-note">
       {posts.length} posts in English and 中文 · <a href="/rss.xml">RSS</a>
     </p>
+    <div class="hero-banner-card">
+      <picture>
+        <source srcset="/images/hero-banner-2x.webp 2048w, /images/hero-banner.webp 1024w" sizes="(max-width: 1120px) 100vw, 1120px" type="image/webp" />
+        <img
+          class="hero-banner-img"
+          src="/images/hero-banner.jpg"
+          alt="From Code to Production — Systems Architecture & DevOps Infrastructure Ecosystem"
+          width="1024"
+          height="572"
+          loading="eager"
+          fetchpriority="high"
+          decoding="async"
+        />
+      </picture>
+    </div>
   </section>
 
   <section id="featured">