feat(ui): Liquid Glass + Aceternity 컴포넌트 도입 (clsx·framer-motion·tailwind-merge)

- LiquidGlass: GlassButton·GlassFilter (Apple Liquid Glass 효과)
- 3d-card-effect: 마우스 추적 3D 카드 래퍼
- sparkles-text: SparklesText·SparklesOverlay
- lib/utils.ts: cn() (clsx + tailwind-merge)

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

package.json

@@ -16,7 +16,9 @@
     "@supabase/ssr": "^0.5.2",
     "@supabase/supabase-js": "^2.99.0",
     "cheerio": "^1.2.0",
+    "clsx": "^2.1.1",
     "dotenv": "^17.3.1",
+    "framer-motion": "^12.38.0",
     "lunar-javascript": "^1.7.7",
     "next": "16.1.6",
     "openai": "^6.21.0",
@@ -25,7 +27,8 @@
     "react-markdown": "^9.0.1",
     "remark-gfm": "^4.0.0",
     "resend": "^6.9.1",
-    "solarlunar": "^2.0.7"
+    "solarlunar": "^2.0.7",
+    "tailwind-merge": "^3.5.0"
   },
   "devDependencies": {
     "@tailwindcss/postcss": "^4",