refactor: resolve all code review feedback (B1-B8 & Option A 5 Pillars) for ANL lab transformation

refer_landing_page/app/intro/_components/HeroComposition.tsx

@@ -1,6 +1,6 @@
 /**
  * Abstract editorial hero — a custom illustration (inline SVG, no asset).
- *   • MCM  → a constellation of interconnected nodes (vermillion).
+ *   • A2A  → a constellation of interconnected nodes (vermillion).
  *   • QUIC → flowing, multiplexed streams (cobalt), animated dash flow.
  * Animations are pure CSS (tailwind keyframes: node-pulse, stream-dash).
  *
@@ -11,7 +11,7 @@ export default function HeroComposition({
 }: {
   className?: string;
 }) {
-  // MCM node coordinates (interconnected mesh, upper-left field).
+  // A2A node coordinates (interconnected mesh, upper-left field).
   const nodes = [
     { x: 70, y: 90 },
     { x: 160, y: 60 },
@@ -36,7 +36,7 @@ export default function HeroComposition({
     <svg
       viewBox="0 0 380 380"
       role="img"
-      aria-label="MCM 상호운용 노드와 QUIC 멀티스트림을 형상화한 추상 일러스트레이션"
+      aria-label="A2A 에이전트 메시와 QUIC/gRPC 멀티스트림을 형상화한 추상 일러스트레이션"
       className={className}
     >
       {/* Frame */}
@@ -66,7 +66,7 @@ export default function HeroComposition({
         })}
       </g>
 
-      {/* ---- MCM: interconnected node mesh (vermillion) ---- */}
+      {/* ---- A2A: interconnected node mesh (vermillion) ---- */}
       <g stroke="#D9342B" strokeWidth="1.5">
         {edges.map(([a, b], i) => (
           <line
@@ -97,12 +97,12 @@ export default function HeroComposition({
       </g>
 
       {/* Annotations — placed in the top corners (y=24), clear of the
-          MCM node mesh (y=60..240) and the QUIC stream curves (y≥250 with
+          A2A node mesh (y=60..240) and the QUIC stream curves (y≥250 with
           control points reaching y+40=380). See LAYOUT_AUDIT #3 and
           REVIEW §3 "P1 #3" — keeping them at y=24 (mirror corners) preserves
           a symmetric layout that the original LAYOUT_AUDIT mirror decided on. */}
       <text x="20" y="24" fill="#0A0A0A" fontSize="11" fontWeight="600" letterSpacing="2">
-        MCM · MESH
+        A2A · MESH
       </text>
       <text
         x="360"