feat: add logo to hero section

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/pages/index.astro

@@ -16,6 +16,11 @@ import Base from "../layouts/Base.astro";
 
   <!-- Hero -->
   <section class="py-16 text-center">
+    <img
+      src="/donglora-logo.jpg"
+      alt="DongLoRa logo"
+      class="w-48 h-48 mx-auto mb-6 rounded-2xl"
+    />
     <h1 class="font-mono text-5xl sm:text-6xl font-bold text-accent mb-4">DongLoRa</h1>
     <p class="text-text-dim text-sm mb-3 italic">/ˈdɒŋ.ɡəl.ɔːr.ə/ — dongle + LoRa</p>
     <p class="text-xl text-text-muted max-w-2xl mx-auto mb-2">