refactor: split modules and harden scraping workflows

web/src/pages/downloadClientPageModel.ts

@@ -0,0 +1,7 @@
+export function apiErrorMessage(err: unknown, fallback: string): string {
+  const data = (err as { response?: { data?: { error?: string; message?: string } } })?.response?.data
+  if (data?.error) return data.error
+  if (data?.message) return data.message
+  if ((err as { code?: string })?.code === 'ECONNABORTED') return '请求超时，请检查服务或网络'
+  return fallback
+}