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+# Excel 导出 xlsx 统一化与前端 CSV 替换 Implementation Plan
+
+> **For agentic workers:** REQUIRED SUB-SKILL: Use superpowers:subagent-driven-development (recommended) or superpowers:executing-plans to implement this plan task-by-task. Steps use checkbox (`- [ ]`) syntax for tracking.
+
+**Goal:** 统一后端 Excel 下载为标准 `.xlsx`，并将 5 个前端页面从本地 CSV 导出切换为后端真实 Excel 导出。
+
+**Architecture:** 后端以 `ExcelUtils` 为唯一公共导出入口，统一 MIME、文件名后缀和可编码文件名策略；前端不再拼接 `csvContent` 或创建 `text/csv` Blob，而是为目标页面新增 API 下载封装，直接请求后端导出接口并复用响应头中的文件名。实现按 backend lane / frontend lane 拆开，但在同一 feature 下联调收口。
+
+**Tech Stack:** Java 17, Spring Boot, EasyExcel, MockMvc, Vue 3, TypeScript, Axios wrapper (`@/config/axios`), pnpm
+
+---
+
+## File Structure
+
+### Backend files
+- Modify: `../water-backend/sw-framework/sw-spring-boot-starter-excel/src/main/java/cn/com/emsoft/sw/framework/excel/core/util/ExcelUtils.java`
+  - 统一 `write` / `writeWithTemplate` / `writeTemplate` 的 xlsx MIME 与 `Content-Disposition`。
+- Modify: `../water-backend/sw-business/sw-business-server/src/test/java/cn/com/emsoft/sw/business/controller/admin/accountingadjust/accountProcess/AccountingAdjustRouteSmokeTest.java`
+  - 把现有导出 smoke 断言从 `application/vnd.ms-excel` 更新为 xlsx MIME，并验证 `Content-Disposition` 仍存在。
+- Inspect/reuse (no code unless缺口真实存在):
+  - `../water-backend/sw-business/sw-business-server/src/main/java/cn/com/emsoft/sw/business/controller/admin/accountingadjust/accountProcess/AccountingAdjustActionController.java`
+  - `../water-backend/sw-business-bank/sw-business-bank-server/src/main/java/cn/com/emsoft/sw/bankbusiness/controller/admin/withholdingbatch/WithholdingBatchController.java`
+  - `../water-backend/sw-business-bank/sw-business-bank-server/src/main/java/cn/com/emsoft/sw/bankbusiness/controller/admin/withholdingitem/WithholdingItemController.java`
+  - `../water-backend/sw-business-bank/sw-business-bank-server/src/main/java/cn/com/emsoft/sw/bankbusiness/controller/admin/channelstatistics/ChannelStatisticsController.java`
+
+### Frontend files
+- Create: `../water-frontend/src/api/operatingCharges/redReversalRecord/index.ts`
+  - 红冲记录页导出 API。
+- Create: `../water-frontend/src/api/collection/export/index.ts`
+  - 银行托收 / 托收明细 / 银行代扣 / 实时收费导出 API。
+- Modify: `../water-frontend/src/utils/download.ts`
+  - 增加从后端响应中提取文件名并下载 Blob 的工具，支持中文文件名编码。
+- Modify: `../water-frontend/src/views/operatingCharges/redReversalRecord/index.vue`
+  - 删除本地 CSV 导出，改调红冲记录导出 API。
+- Modify: `../water-frontend/src/views/collection/bankCollection/index.vue`
+  - 删除本地 CSV 导出，改调托收批次导出 API。
+- Modify: `../water-frontend/src/views/collection/bankCollection/detail.vue`
+  - 删除本地 CSV 导出，改调托收明细导出 API。
+- Modify: `../water-frontend/src/views/collection/bankWithholding/index.vue`
+  - 删除本地 CSV 导出，改调用同一批次导出 API，并带 `businessType=WITHHOLDING`。
+- Modify: `../water-frontend/src/views/collection/realTimeBilling/index.vue`
+  - 删除本地 CSV 导出，改调实时收费统计导出 API。
+
+---
+
+### Task 1: 统一后端 ExcelUtils 为标准 xlsx 下载
+
+**Files:**
+- Modify: `../water-backend/sw-framework/sw-spring-boot-starter-excel/src/main/java/cn/com/emsoft/sw/framework/excel/core/util/ExcelUtils.java`
+- Test: `../water-backend/sw-business/sw-business-server/src/test/java/cn/com/emsoft/sw/business/controller/admin/accountingadjust/accountProcess/AccountingAdjustRouteSmokeTest.java`
+
+- [ ] **Step 1: 先写出会失败的导出头断言**
+
+在 `AccountingAdjustRouteSmokeTest.java` 把 4 个导出断言先改成 xlsx MIME，保持其它断言不动：
+
+```java
+mockMvc.perform(get(BASE + "/log-export"))
+        .andExpect(status().isOk())
+        .andExpect(header().string("Content-Disposition", org.hamcrest.Matchers.startsWith("attachment;filename=")))
+        .andExpect(content().contentType("application/vnd.openxmlformats-officedocument.spreadsheetml.sheet;charset=UTF-8"));
+
+mockMvc.perform(get(BASE + "/log-export-excel"))
+        .andExpect(status().isOk())
+        .andExpect(header().string("Content-Disposition", org.hamcrest.Matchers.startsWith("attachment;filename=")))
+        .andExpect(content().contentType("application/vnd.openxmlformats-officedocument.spreadsheetml.sheet;charset=UTF-8"));
+
+mockMvc.perform(get(BASE + "/prestorage-export"))
+        .andExpect(status().isOk())
+        .andExpect(header().string("Content-Disposition", org.hamcrest.Matchers.startsWith("attachment;filename=")))
+        .andExpect(content().contentType("application/vnd.openxmlformats-officedocument.spreadsheetml.sheet;charset=UTF-8"));
+
+mockMvc.perform(get(BASE + "/prestorage-export-excel"))
+        .andExpect(status().isOk())
+        .andExpect(header().string("Content-Disposition", org.hamcrest.Matchers.startsWith("attachment;filename=")))
+        .andExpect(content().contentType("application/vnd.openxmlformats-officedocument.spreadsheetml.sheet;charset=UTF-8"));
+```
+
+- [ ] **Step 2: 运行后端 smoke，确认当前实现失败**
+
+Run:
+
+```bash
+mvn -f "/Volumes/Dpan/github/water-workspace/water-backend/pom.xml" -pl sw-business/sw-business-server -am -Dtest=AccountingAdjustRouteSmokeTest test
+```
+
+Expected: FAIL，错误类似 `Content type expected:<application/vnd.openxmlformats-officedocument.spreadsheetml.sheet;charset=UTF-8> but was:<application/vnd.ms-excel;charset=UTF-8>`。
+
+- [ ] **Step 3: 在 ExcelUtils 中抽出统一下载头设置方法，并把 MIME 改成 xlsx**
+
+把 `ExcelUtils.java` 的响应头逻辑改成下面这种结构，三个写方法都复用它：
+
+```java
+private static final String XLSX_CONTENT_TYPE =
+        "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet;charset=UTF-8";
+
+private static void prepareAttachmentResponse(HttpServletResponse response, String filename) {
+    response.addHeader("Content-Disposition", "attachment;filename=" + HttpUtils.encodeUtf8(ensureXlsxFilename(filename)));
+    response.setContentType(XLSX_CONTENT_TYPE);
+}
+
+private static String ensureXlsxFilename(String filename) {
+    if (filename == null || filename.isBlank()) {
+        return "export.xlsx";
+    }
+    if (filename.toLowerCase().endsWith(".xlsx")) {
+        return filename;
+    }
+    if (filename.toLowerCase().endsWith(".xls")) {
+        return filename.substring(0, filename.length() - 4) + ".xlsx";
+    }
+    return filename + ".xlsx";
+}
+```
+
+然后把三个入口统一改成：
+
+```java
+public static <T> void write(HttpServletResponse response, String filename, String sheetName,
+                             Class<T> head, List<T> data) throws IOException {
+    prepareAttachmentResponse(response, filename);
+    EasyExcel.write(response.getOutputStream(), head)
+            .autoCloseStream(false)
+            .registerWriteHandler(new LongestMatchColumnWidthStyleStrategy())
+            .registerWriteHandler(new SelectSheetWriteHandler(head))
+            .registerConverter(new LongStringConverter())
+            .sheet(sheetName)
+            .doWrite(data);
+}
+```
+
+```java
+public static <T> void writeWithTemplate(HttpServletResponse response, String filename, InputStream templateStream,
+                                         String sheetName, Class<T> head, List<T> data) throws IOException {
+    if (templateStream == null) {
+        throw new RuntimeException("Excel模板文件流不能为空");
+    }
+    prepareAttachmentResponse(response, filename);
+    try (templateStream) {
+        EasyExcel.write(response.getOutputStream(), head)
+                .withTemplate(templateStream)
+                .autoCloseStream(false)
+                .registerWriteHandler(new SelectSheetWriteHandler(head))
+                .registerConverter(new LongStringConverter())
+                .sheet(sheetName)
+                .needHead(false)
+                .doWrite(data);
+    }
+}
+```
+
+```java
+public static void writeTemplate(HttpServletResponse response, String filename, InputStream templateStream)
+        throws IOException {
+    prepareAttachmentResponse(response, filename);
+    templateStream.transferTo(response.getOutputStream());
+    templateStream.close();
+}
+```
+
+- [ ] **Step 4: 重新跑后端 smoke，确认通过**
+
+Run:
+
+```bash
+mvn -f "/Volumes/Dpan/github/water-workspace/water-backend/pom.xml" -pl sw-business/sw-business-server -am -Dtest=AccountingAdjustRouteSmokeTest test
+```
+
+Expected: PASS，四个导出断言均匹配 xlsx MIME。
+
+- [ ] **Step 5: 提交后端公共导出修复**
+
+```bash
+git -C "/Volumes/Dpan/github/water-workspace/water-backend" add \
+  sw-framework/sw-spring-boot-starter-excel/src/main/java/cn/com/emsoft/sw/framework/excel/core/util/ExcelUtils.java \
+  sw-business/sw-business-server/src/test/java/cn/com/emsoft/sw/business/controller/admin/accountingadjust/accountProcess/AccountingAdjustRouteSmokeTest.java
+
+git -C "/Volumes/Dpan/github/water-workspace/water-backend" commit -m "fix(excel): standardize xlsx download headers"
+```
+
+### Task 2: 给前端下载工具增加后端文件流下载与文件名解码
+
+**Files:**
+- Modify: `../water-frontend/src/utils/download.ts`
+- Test: `../water-frontend/src/views/operatingCharges/redReversalRecord/index.vue` (first consumer)
+
+- [ ] **Step 1: 为下载工具写出目标接口**
+
+在 `download.ts` 里新增两个内部函数：一个解析 `Content-Disposition`，一个下载 axios blob 响应。目标代码如下：
+
+```ts
+const decodeFilename = (contentDisposition?: string, fallbackName = 'export.xlsx') => {
+  if (!contentDisposition) return fallbackName
+  const utf8Match = contentDisposition.match(/filename\*=utf-8''([^;]+)/i)
+  if (utf8Match?.[1]) {
+    return decodeURIComponent(utf8Match[1])
+  }
+  const plainMatch = contentDisposition.match(/filename=([^;]+)/i)
+  if (plainMatch?.[1]) {
+    return decodeURIComponent(plainMatch[1].trim().replace(/^"|"$/g, ''))
+  }
+  return fallbackName
+}
+
+const downloadResponse = (response: any, fallbackName = 'export.xlsx') => {
+  const fileName = decodeFilename(response?.headers?.['content-disposition'], fallbackName)
+  download0(response.data, fileName, response.data?.type || 'application/octet-stream')
+}
+```
+
+- [ ] **Step 2: 把新工具挂到默认导出对象**
+
+在 `download` 对象中追加：
+
+```ts
+response: (response: any, fallbackName?: string) => {
+  downloadResponse(response, fallbackName)
+}
+```
+
+保留原有 `excel/word/zip/html/markdown/json`，不要顺手改其它行为。
+
+- [ ] **Step 3: 运行前端类型检查，确认工具签名可用**
+
+Run:
+
+```bash
+pnpm --dir "/Volumes/Dpan/github/water-workspace/water-frontend" ts:check
+```
+
+Expected: PASS；如果有 `response` 未使用或 `any` 风格告警，只修本次新增代码，不扩散重构。
+
+- [ ] **Step 4: 提交前端下载工具改动**
+
+```bash
+git -C "/Volumes/Dpan/github/water-workspace/water-frontend" add src/utils/download.ts
+
+git -C "/Volumes/Dpan/github/water-workspace/water-frontend" commit -m "feat(download): support backend blob responses"
+```
+
+### Task 3: 新增前端导出 API 封装并替换红冲记录页
+
+**Files:**
+- Create: `../water-frontend/src/api/operatingCharges/redReversalRecord/index.ts`
+- Modify: `../water-frontend/src/views/operatingCharges/redReversalRecord/index.vue`
+
+- [ ] **Step 1: 新建红冲记录导出 API 文件**
+
+创建 `src/api/operatingCharges/redReversalRecord/index.ts`：
+
+```ts
+import request from '@/config/axios'
+
+export const exportRedReversalRecord = (params: any) => {
+  return request.download({
+    url: '/business/accounting-adjust/log-export',
+    params
+  })
+}
+```
+
+- [ ] **Step 2: 先删掉红冲记录页本地 CSV 构造，替换为后端下载调用**
+
+把 `redReversalRecord/index.vue` 的导出逻辑改成：
+
+```ts
+import download from '@/utils/download'
+import { exportRedReversalRecord } from '@/api/operatingCharges/redReversalRecord'
+```
+
+```ts
+const handleExport = async () => {
+  try {
+    await message.exportConfirm()
+    exportLoading.value = true
+    const response = await exportRedReversalRecord({ ...queryParams })
+    download.response(response, `红冲记录_${formatDate(Date.now() as any)}.xlsx`)
+  } finally {
+    exportLoading.value = false
+  }
+}
+```
+
+同时删除这些旧代码：
+
+```ts
+const data = list.value
+const headers = ['红冲时间', '红冲金额', '收费员', '操作员', '收费时间', '备注']
+const csvContent = [
+  headers.join(','),
+  ...data.map((row: any) => [
+    row.reversalTime,
+    row.reversalAmount,
+    row.cashier,
+    row.operator,
+    row.chargeTime,
+    row.remark
+  ].join(','))
+].join('\n')
+const blob = new Blob(['\ufeff' + csvContent], { type: 'text/csv;charset=utf-8;' })
+download.excel(blob, `红冲记录_${formatDate(Date.now() as any)}.csv`)
+```
+
+- [ ] **Step 3: 运行前端类型检查，确认红冲记录页接线通过**
+
+Run:
+
+```bash
+pnpm --dir "/Volumes/Dpan/github/water-workspace/water-frontend" ts:check
+```
+
+Expected: PASS；页面仍可编译，新增 API 路径可被解析。
+
+- [ ] **Step 4: 提交红冲记录页接线**
+
+```bash
+git -C "/Volumes/Dpan/github/water-workspace/water-frontend" add \
+  src/api/operatingCharges/redReversalRecord/index.ts \
+  src/views/operatingCharges/redReversalRecord/index.vue
+
+git -C "/Volumes/Dpan/github/water-workspace/water-frontend" commit -m "feat(red-reversal): use backend excel export"
+```
+
+### Task 4: 新增 collection 导出 API 并替换托收批次/托收明细页面
+
+**Files:**
+- Create: `../water-frontend/src/api/collection/export/index.ts`
+- Modify: `../water-frontend/src/views/collection/bankCollection/index.vue`
+- Modify: `../water-frontend/src/views/collection/bankCollection/detail.vue`
+
+- [ ] **Step 1: 新建 collection 导出 API 文件**
+
+创建 `src/api/collection/export/index.ts`：
+
+```ts
+import request from '@/config/axios'
+
+export const exportCollectionBatch = (params: any) => {
+  return request.download({
+    url: '/bankbusiness/withholding-batch/export-excel',
+    params: {
+      ...params,
+      businessType: 'COLLECTION'
+    }
+  })
+}
+
+export const exportCollectionDetail = (params: any) => {
+  return request.download({
+    url: '/bankbusiness/withholding-item/export-excel',
+    params
+  })
+}
+
+export const exportWithholdingBatch = (params: any) => {
+  return request.download({
+    url: '/bankbusiness/withholding-batch/export-excel',
+    params: {
+      ...params,
+      businessType: 'WITHHOLDING'
+    }
+  })
+}
+
+export const exportRealtimeStatistics = (params: any) => {
+  return request.download({
+    url: '/bankbusiness/channel-statistics/export-excel',
+    params
+  })
+}
+```
+
+- [ ] **Step 2: 替换银行托收页导出**
+
+在 `bankCollection/index.vue` 中引入：
+
+```ts
+import download from '@/utils/download'
+import { exportCollectionBatch } from '@/api/collection/export'
+```
+
+把导出函数改成：
+
+```ts
+const handleExport = async () => {
+  try {
+    await message.exportConfirm()
+    exportLoading.value = true
+    const response = await exportCollectionBatch({ ...queryParams })
+    download.response(response, `银行托收_${formatDate(Date.now() as any)}.xlsx`)
+  } finally {
+    exportLoading.value = false
+  }
+}
+```
+
+删除 `headers.join(',')` / `csvContent` / `Blob(text/csv)` / `.csv` 文件名代码。
+
+- [ ] **Step 3: 替换托收明细页导出**
+
+在 `bankCollection/detail.vue` 中引入：
+
+```ts
+import download from '@/utils/download'
+import { exportCollectionDetail } from '@/api/collection/export'
+```
+
+把导出函数改成：
+
+```ts
+const handleExport = async () => {
+  try {
+    await message.exportConfirm()
+    exportLoading.value = true
+    const response = await exportCollectionDetail({ ...queryParams })
+    download.response(response, `托收明细_${formatDate(Date.now() as any)}.xlsx`)
+  } finally {
+    exportLoading.value = false
+  }
+}
+```
+
+保留 `batchNo: route.query.batchNo || ''` 作为请求参数的一部分，不要丢掉详情上下文。
+
+- [ ] **Step 4: 运行前端类型检查，确认两个页面通过**
+
+Run:
+
+```bash
+pnpm --dir "/Volumes/Dpan/github/water-workspace/water-frontend" ts:check
+```
+
+Expected: PASS；`bankCollection` 与 `detail` 不再包含 CSV 导出逻辑。
+
+- [ ] **Step 5: 提交托收页面改造**
+
+```bash
+git -C "/Volumes/Dpan/github/water-workspace/water-frontend" add \
+  src/api/collection/export/index.ts \
+  src/views/collection/bankCollection/index.vue \
+  src/views/collection/bankCollection/detail.vue
+
+git -C "/Volumes/Dpan/github/water-workspace/water-frontend" commit -m "feat(collection): switch batch exports to backend excel"
+```
+
+### Task 5: 替换银行代扣与实时收费页面导出
+
+**Files:**
+- Modify: `../water-frontend/src/views/collection/bankWithholding/index.vue`
+- Modify: `../water-frontend/src/views/collection/realTimeBilling/index.vue`
+- Reuse: `../water-frontend/src/api/collection/export/index.ts`
+
+- [ ] **Step 1: 替换银行代扣页导出**
+
+在 `bankWithholding/index.vue` 中引入：
+
+```ts
+import download from '@/utils/download'
+import { exportWithholdingBatch } from '@/api/collection/export'
+```
+
+把导出函数改成：
+
+```ts
+const handleExport = async () => {
+  try {
+    await message.exportConfirm()
+    exportLoading.value = true
+    const response = await exportWithholdingBatch({ ...queryParams })
+    download.response(response, `银行代扣_${formatDate(Date.now() as any)}.xlsx`)
+  } finally {
+    exportLoading.value = false
+  }
+}
+```
+
+删除本地 CSV 生成代码。
+
+- [ ] **Step 2: 替换实时收费页导出**
+
+在 `realTimeBilling/index.vue` 中引入：
+
+```ts
+import download from '@/utils/download'
+import { exportRealtimeStatistics } from '@/api/collection/export'
+```
+
+把导出函数改成：
+
+```ts
+const handleExport = async () => {
+  try {
+    await message.exportConfirm()
+    exportLoading.value = true
+    const response = await exportRealtimeStatistics({ ...queryParams })
+    download.response(response, `实时收费_${formatDate(Date.now() as any)}.xlsx`)
+  } finally {
+    exportLoading.value = false
+  }
+}
+```
+
+删除原 `csvContent` / `Blob(text/csv)` 代码。
+
+- [ ] **Step 3: 跑前端类型检查与最小构建**
+
+Run:
+
+```bash
+pnpm --dir "/Volumes/Dpan/github/water-workspace/water-frontend" ts:check
+pnpm --dir "/Volumes/Dpan/github/water-workspace/water-frontend" build:dev
+```
+
+Expected: 两条命令都 PASS；`build:dev` 产物成功生成。
+
+- [ ] **Step 4: 提交银行代扣与实时收费页改造**
+
+```bash
+git -C "/Volumes/Dpan/github/water-workspace/water-frontend" add \
+  src/views/collection/bankWithholding/index.vue \
+  src/views/collection/realTimeBilling/index.vue
+
+git -C "/Volumes/Dpan/github/water-workspace/water-frontend" commit -m "feat(collection): route remaining exports through backend"
+```
+
+### Task 6: 联调验证与收口
+
+**Files:**
+- Verify: `../water-backend/...` changed files
+- Verify: `../water-frontend/...` changed files
+- Optional evidence note: `../water-docs/docs/evidence/` (only if user asks for persistent evidence)
+
+- [ ] **Step 1: 手工检查代码中已消失的 CSV 痕迹**
+
+Run:
+
+```bash
+grep -R "text/csv\|csvContent\|\.csv" "/Volumes/Dpan/github/water-workspace/water-frontend/src/views/operatingCharges/redReversalRecord" \
+  "/Volumes/Dpan/github/water-workspace/water-frontend/src/views/collection/bankCollection" \
+  "/Volumes/Dpan/github/water-workspace/water-frontend/src/views/collection/bankWithholding" \
+  "/Volumes/Dpan/github/water-workspace/water-frontend/src/views/collection/realTimeBilling"
+```
+
+Expected: 无匹配，或者仅剩注释/字符串字面量以外的历史内容为 0。
+
+- [ ] **Step 2: 手工检查后端 xlsx MIME 已生效**
+
+Run:
+
+```bash
+grep -R "application/vnd.ms-excel;charset=UTF-8" "/Volumes/Dpan/github/water-workspace/water-backend/sw-framework/sw-spring-boot-starter-excel/src/main/java/cn/com/emsoft/sw/framework/excel/core/util/ExcelUtils.java"
+```
+
+Expected: 无匹配。
+
+- [ ] **Step 3: 浏览器 smoke**
+
+在本地/测试环境逐页点击导出并记录结果：
+
+- `/operatingCharges/redReversalRecord`
+- `/collection/bankCollection`
+- `/collection/bankCollection/detail?batchNo=<sample>`
+- `/collection/bankWithholding`
+- `/collection/realTimeBilling`
+
+Expected:
+- 发起真实网络请求，不是浏览器本地 Blob 生成。
+- 返回文件为 `.xlsx`。
+- 中文文件名不乱码。
+
+- [ ] **Step 4: 分别查看两仓状态并准备后续 PR**
+
+Run:
+
+```bash
+git -C "/Volumes/Dpan/github/water-workspace/water-backend" status --short
+
+git -C "/Volumes/Dpan/github/water-workspace/water-frontend" status --short
+```
+
+Expected: 两仓仅包含本计划涉及的文件改动，无额外脏改动。
+
+- [ ] **Step 5: 如果需要合并前整理最终提交**
+
+```bash
+git -C "/Volumes/Dpan/github/water-workspace/water-backend" log --oneline -3
+
+git -C "/Volumes/Dpan/github/water-workspace/water-frontend" log --oneline -5
+```
+
+Expected: 后端至少 1 个导出统一提交，前端至少 3 个渐进提交（下载工具、红冲记录、collection 页面）。
+
+---
+
+## Self-Review
+
+- **Spec coverage:**
+  - FR-001/FR-002/FR-011/SC-001/SC-006 → Task 1
+  - FR-003/FR-004/FR-005/FR-008/SC-002/SC-003 → Tasks 2-5
+  - FR-006/FR-007/SC-004 → Tasks 3-5 通过明确 API 路径落地
+  - FR-009/FR-010/FR-012/SC-005 → Task 6 + 提交拆分策略
+- **Placeholder scan:** 已避免使用 TBD/TODO/“类似 Task N”；每个改代码步骤都给了具体代码片段。
+- **Type consistency:** 统一使用 `download.response(...)` 处理后端 blob 响应；前端导出 API 全部基于 `request.download(...)`。