feat: 添加 Anki APKG 导入/导出功能

- 添加 APKG 解析器 (src/lib/anki/apkg-parser.ts)
- 添加 APKG 导出器 (src/lib/anki/apkg-exporter.ts)
- 添加导入/导出 Server Actions
- 添加导入/导出 UI 组件
- 集成到牌组页面
- 添加 i18n 翻译

同时修复断链:
- /folders → /decks (Navbar, signup, profile)

package.json

@@ -18,6 +18,7 @@
     "class-variance-authority": "^0.7.1",
     "clsx": "^2.1.1",
     "dotenv": "^17.2.3",
+    "jszip": "^3.10.1",
     "lucide-react": "^0.562.0",
     "next": "16.1.1",
     "next-intl": "^4.7.0",
@@ -27,6 +28,7 @@
     "react": "19.2.3",
     "react-dom": "19.2.3",
     "sonner": "^2.0.7",
+    "sql.js": "^1.14.1",
     "tailwind-merge": "^3.4.0",
     "unstorage": "^1.17.3",
     "winston": "^3.19.0",
@@ -41,6 +43,7 @@
     "@types/nodemailer": "^7.0.11",
     "@types/react": "19.2.7",
     "@types/react-dom": "19.2.3",
+    "@types/sql.js": "^1.4.9",
     "@typescript-eslint/eslint-plugin": "^8.51.0",
     "@typescript-eslint/parser": "^8.51.0",
     "babel-plugin-react-compiler": "^1.0.0",