refactor(animations): converge P1 motion durations to ≤300ms target

- 151 scripted + 1 manual duration fixes across 46 files
- framer entrance 0.5/0.6s -> 0.3s
- Tailwind hover -> duration-150, entrance -> duration-300
- preserve flip-clock/page-transition per semantic decision
- design-system.ts dead-code deferred
- P1 violations 156 -> 5; P0 remains 0; OK class 249 -> 400
- verified: tsc clean, eslint 0 errors
- verified: 130/130 jest suites, 1573 passed
- verified: visual regression 46/46 zero-pixel diff

Co-Authored-By: 阿睿 <workbuddy@tencent.com>

src/components/sections/methodology-section.tsx

@@ -19,7 +19,7 @@ export function MethodologySection() {
         <motion.div
           initial={{ opacity: 0, y: 20 }}
           animate={isInView ? { opacity: 1, y: 0 } : {}}
-          transition={{ duration: 0.5, ease: [0.16, 1, 0.3, 1] }}
+          transition={{ duration: 0.3, ease: [0.16, 1, 0.3, 1] }}
           className="text-center max-w-3xl mx-auto mb-14"
         >
           <h2 id="methodology-heading" className="text-3xl sm:text-4xl font-semibold text-[var(--color-text-primary)] mb-4">