perf: finalize PageSpeed 100 and WCAG 2.1 AA stabilization

- Achieved 100/100 Accessibility score across sitemap (pa11y-ci 10/10 parity)
- Stabilized Performance score >= 94 by purging LCP-blocking CSS animations
- Fixed canonical/hreflang absolute URI mismatches for perfect SEO scores
- Silenced client-side telemetry/analytics console noise in CI environments
- Hardened sitemap generation with environment-aware baseUrl
- Refined contrast for Badge and VisualLinkPreview components (#14532d)

app/[locale]/blog/page.tsx

@@ -65,7 +65,7 @@ export default async function BlogIndex({ params }: BlogIndexProps) {
                 src={featuredPost.frontmatter.featuredImage}
                 alt={featuredPost.frontmatter.title}
                 fill
-                className="absolute inset-0 w-full h-full object-cover scale-105 animate-slow-zoom opacity-40 md:opacity-60"
+                className="absolute inset-0 w-full h-full object-cover opacity-40 md:opacity-60"
                 sizes="100vw"
                 priority
               />
@@ -74,7 +74,7 @@ export default async function BlogIndex({ params }: BlogIndexProps) {
           )}
 
           <Container className="relative z-10">
-            <div className="max-w-4xl animate-slide-up">
+            <div className="max-w-4xl">
               <div className="flex flex-wrap items-center gap-3 mb-4 md:mb-6">
                 <Badge variant="saturated">{t('featuredPost')}</Badge>
                 {featuredPost &&
@@ -177,13 +177,13 @@ export default async function BlogIndex({ params }: BlogIndexProps) {
                         )}
                         {(new Date(post.frontmatter.date) > new Date() ||
                           post.frontmatter.public === false) && (
-                            <Badge
-                              variant="accent"
-                              className="absolute top-3 right-3 md:top-6 md:right-6 shadow-lg bg-orange-500 text-white border-none"
-                            >
-                              Preview
-                            </Badge>
-                          )}
+                          <Badge
+                            variant="accent"
+                            className="absolute top-3 right-3 md:top-6 md:right-6 shadow-lg bg-orange-500 text-white border-none"
+                          >
+                            Preview
+                          </Badge>
+                        )}
                       </div>
                     )}
                     <div className="p-5 md:p-10 flex flex-col flex-1">