feat(grilles): replace plastic content image with round diffuser photos

- Swap grilles-plastic-content.jpg for round-grille-front + round-grille-angle
- Two round images on their own row, 211x211px, equal height

src/pages/grilles.astro

@@ -150,7 +150,10 @@ import BaseLayout from '@/layouts/BaseLayout.astro';
 
             <div class="flex flex-wrap justify-center gap-4 my-8">
               <img src="/images/grilles/fresh-air1-content-1.jpg" alt="Fresh Air" class="max-w-md w-full h-auto rounded-lg shadow-md" width="400" height="300" loading="lazy" />
-              <img src="/images/grilles/grilles-plastic-content.jpg" alt="กริลแอร์พลาสติก" class="max-w-md w-full h-auto rounded-lg shadow-md" width="400" height="300" loading="lazy" />
+            </div>
+            <div class="flex flex-wrap items-center justify-center gap-4 my-8 -mt-4">
+              <img src="/images/grilles/round-grille-front.jpg" alt="หน้ากากแอร์ทรงกลม (Round Diffuser) ด้านหน้า" class="h-[211px] w-[211px] flex-shrink-0 object-cover rounded-lg shadow-md" loading="lazy" decoding="async" />
+              <img src="/images/grilles/round-grille-angle.jpg" alt="หน้ากากแอร์ทรงกลม (Round Diffuser) มุมเอียง" class="h-[211px] w-[211px] flex-shrink-0 object-cover rounded-lg shadow-md" loading="lazy" decoding="async" />
             </div>
 
             <h3 class="text-xl font-bold text-primary-700 mt-8 mb-4">ประเภทของหน้ากากแอร์</h3>