perf: optimize Lighthouse scores to 100

Performance:
- Lazy-load ShaderGradientBackground via dynamic import (reduces initial JS ~250KB)
- Disable ShaderGradient animations (animate=off) to reduce CPU/GPU load
- Remove opacity:0 animations from Hero LCP elements for instant paint
- Add browserslist targeting modern browsers (eliminates ~13KB polyfills)

Accessibility:
- Fix color contrast: text-stone-400 → text-stone-600 dark:text-stone-400 on light backgrounds
- Fix text-liquid-mint → text-emerald-700/600 for readable text/accent dots
- Fix quote text contrast on dark status box (text-stone-700 → text-stone-300)
- Fix Online badge contrast (emerald-600 → emerald-700)

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

app/components/Hero.tsx

@@ -58,16 +58,16 @@ const Hero = () => {
 
             <h1 className="text-[2.75rem] sm:text-6xl md:text-8xl lg:text-[9.5rem] font-black tracking-tighter leading-[0.85] text-stone-900 dark:text-stone-50 uppercase">
               <motion.span
-                initial={{ opacity: 0, x: -50 }}
-                animate={{ opacity: 1, x: 0 }}
+                initial={{ x: -50 }}
+                animate={{ x: 0 }}
                 transition={{ duration: 0.8, delay: 0.1 }}
                 className="block"
               >
                 {getLabel("hero.line1", "Building")}
               </motion.span>
               <motion.span
-                initial={{ opacity: 0, x: -50 }}
-                animate={{ opacity: 1, x: 0 }}
+                initial={{ x: -50 }}
+                animate={{ x: 0 }}
                 transition={{ duration: 0.8, delay: 0.2 }}
                 className="block text-transparent bg-clip-text bg-gradient-to-r from-emerald-400 via-liquid-sky to-liquid-purple pb-2 sm:pb-4"
               >
@@ -75,14 +75,9 @@ const Hero = () => {
               </motion.span>
             </h1>
 
-            <motion.p
-              initial={{ opacity: 0 }}
-              animate={{ opacity: 1 }}
-              transition={{ duration: 1, delay: 0.4 }}
-              className="text-base sm:text-lg md:text-xl lg:text-2xl text-stone-600 dark:text-stone-400 max-w-xl mx-auto lg:mx-0 font-light leading-relaxed tracking-tight"
-            >
+            <p className="text-base sm:text-lg md:text-xl lg:text-2xl text-stone-600 dark:text-stone-400 max-w-xl mx-auto lg:mx-0 font-light leading-relaxed tracking-tight">
               {t("description")}
-            </motion.p>
+            </p>
 
             <motion.div
               initial={{ opacity: 0, y: 20 }}