fix: 支持备份恢复与站点同步的大文件上传 版本更新到1.5.4

- 备份恢复的 multipart 分支改用 Web FormData，移除旧解析器约 128 MB 的限制
- 初始化恢复新增 application/octet-stream 流式写盘，前端改为直接上传文件流，避免整包进入内存
- 站点同步改用 Web FormData，并在读取请求体前拒绝超过 500 MB 的文件
- 新增 multipart 字段、重复字段和文件读取回归测试

验证：
- 2 GB 测试备份包流式恢复预览成功，服务内存保持低位
- 130 MB 站点同步上传成功
- 原有备份预览及图片、视频、文件上传正常
- npm test 234 项通过；npm run typecheck 与 eslint 通过

server/api/setup/restore.post.ts

@@ -1,25 +1,45 @@
+import { getHeader, readFormData, type H3Event } from 'h3'
 import { createApiError } from '../../utils/api-error'
 import { isInitialized } from '../../utils/auth'
 import { serializeBackupJob } from '../../utils/backup/api'
 import { startFullRestoreJob } from '../../utils/backup/runner'
 import { BACKUP_ARCHIVE_EXT, getBackupsDir } from '../../utils/backup/paths'
+import { readFormDataFiles } from '../../utils/multipart-form'
 import { join } from 'node:path'
-import { promises as fs } from 'node:fs'
+import { createWriteStream, promises as fs } from 'node:fs'
+import { pipeline } from 'node:stream/promises'
+
+async function saveRestoreUpload(event: H3Event, archivePath: string): Promise<void> {
+  const contentType = getHeader(event, 'content-type') ?? ''
+  try {
+    if (contentType.includes('application/octet-stream')) {
+      await pipeline(event.node.req, createWriteStream(archivePath))
+    } else {
+      const form = await readFormData(event)
+      const file = readFormDataFiles(form, ['file'])[0]
+      if (!file) {
+        createApiError(event, 'INVALID_REQUEST', '请上传备份文件', 400)
+      }
+      await fs.writeFile(archivePath, new Uint8Array(await file.arrayBuffer()))
+    }
+    const stat = await fs.stat(archivePath)
+    if (stat.size === 0) {
+      createApiError(event, 'INVALID_REQUEST', '备份文件为空', 400)
+    }
+  } catch (error) {
+    await fs.rm(archivePath, { force: true }).catch(() => {})
+    throw error
+  }
+}
 
 export default defineEventHandler(async (event) => {
   if (isInitialized()) {
     createApiError(event, 'FORBIDDEN', '系统已初始化，请在存储页恢复备份', 403)
   }
 
-  const form = await readMultipartFormData(event)
-  const filePart = form?.find(part => part.name === 'file' && part.data?.length)
-  if (!filePart?.data) {
-    createApiError(event, 'INVALID_REQUEST', '请上传备份文件', 400)
-  }
-
   await fs.mkdir(getBackupsDir(), { recursive: true })
   const archivePath = join(getBackupsDir(), `setup-restore-${Date.now()}${BACKUP_ARCHIVE_EXT}`)
-  await fs.writeFile(archivePath, filePart.data)
+  await saveRestoreUpload(event, archivePath)
 
   try {
     const job = startFullRestoreJob(archivePath, 'overwrite')