fix: 报表Excel导出文件后缀错误-后端生成的是真正的xlsx格式,下载文件名由.xls改为.xlsx(消除格式与扩展名不匹配/被识别为文本的问题)

Co-Authored-By: Claude Code <noreply@anthropic.com>

Author: pythonHuang

JuggleNet6.Frontend/src/views/report/ReportList.vue

@@ -118,7 +118,7 @@ async function doExportPdf(row: any) {
 
 async function doExportExcel(row: any) {
   const res: any = await request.post('/report/export-excel', { id: row.id, params: {} }, { responseType: 'blob' })
-  downloadBlob(res.data, `${row.name}.xls`)
+  downloadBlob(res.data, `${row.name}.xlsx`)
 }
 
 /** 打印：取预览 HTML 写入新窗口并触发浏览器打印 */