feat(i18n): add multi-language UI support with 5 languages

- Add i18n framework with locale detection and cookie persistence
- Support English, Traditional Chinese (zh-TW), Simplified Chinese (zh-CN), Japanese (ja), Korean (ko)
- Add LanguageSelector component in navigation header
- Create locale JSON files with full translations
- Update all page components (root, user, results, history) with i18n support
- Add client-side translation helpers for dynamic content
- Auto-detect user's preferred language from browser settings
- Bump version to v0.1.3

package.json

@@ -1,6 +1,6 @@
 {
   "name": "convertx-frontend",
-  "version": "0.17.0",
+  "version": "0.1.3",
   "scripts": {
     "dev": "bun run --watch src/index.tsx",
     "hot": "bun run --hot src/index.tsx",
@@ -20,6 +20,7 @@
     "@elysiajs/jwt": "^1.4.0",
     "@elysiajs/static": "^1.4.6",
     "@kitajs/html": "^4.2.11",
+    "@sinclair/typebox": "^0.34.47",
     "elysia": "^1.4.16",
     "sanitize-filename": "^1.6.3",
     "tar": "^7.5.2"