feat(frontend): 认证体系 + 类型定义 + API 服务层

认证:
- AuthContext + useAuth (JWT token 持久化, 登录/登出)
- AdminLoginPage (登录表单, 对接 POST /auth/login)
- axios 拦截器自动注入 Authorization header
- 401 自动清除 token 并跳转登录页

类型:
- api.ts: TASK_STATUS 常量, TaskResponse/ProductScanResponse 扩展字段
- admin.ts: ProductResponse 扩展 + MaterialOption/BomItem

API 服务:
- authApi: login() + getMe()
- materialApi: fetchMaterialGroups() + fetchMaterialItems()
- printApi: getLabelPreview() + executePrint() + getPrinterConfig()
- antd 6.5.3 依赖

字体: simhei.ttf (标签打印用)

frontend/package.json

@@ -18,6 +18,7 @@
     "@tailwindcss/vite": "^4.3.3",
     "@tauri-apps/api": "^2.11.1",
     "@tauri-apps/plugin-shell": "^2.3.5",
+    "antd": "^6.5.3",
     "axios": "^1.19.0",
     "html5-qrcode": "^2.3.8",
     "lucide-react": "^1.28.0",