feat: add i18n support with Chinese/English translations

package.json

@@ -26,11 +26,14 @@
     "class-variance-authority": "^0.7.1",
     "clsx": "^2.1.1",
     "dompurify": "^3.4.11",
+    "i18next": "^26.3.1",
+    "i18next-browser-languagedetector": "^8.2.1",
     "lucide-react": "^1.21.0",
     "marked": "^18.0.5",
     "radix-ui": "^1.6.0",
     "react": "^19.2.7",
     "react-dom": "^19.2.7",
+    "react-i18next": "^17.0.8",
     "tailwind-merge": "^3.6.0",
     "tailwindcss": "^4.3.1",
     "zod": "^4.4.3"