feat: 完善媒体管理与备份迁移流程

- 视频上传生成缩略图并提供占位封面和失败原因展示
- 支持 HLS 按需重新封装 MP4，并限制临时文件生命周期与访问权限
- 完善视频、文件 API 文档、搜索、批量删除和单次转码质量参数
- 修复备份恢复与跨后端迁移遗漏缩略图、HLS 清单和分片的问题
- 将备份任务、归档和下载权限按用户隔离
- 增加仅清理当前用户数据的高危存储清空流程和二次文字确认
- 修复 S3 中文文件名元数据及 CLI 数据库连接问题
- 补充备份恢复、用户隔离、媒体资源和转码相关测试

server/utils/backup/full-export.ts

@@ -1,5 +1,5 @@
 import { createWriteStream, promises as fs } from 'node:fs'
-import { basename, join } from 'node:path'
+import { join } from 'node:path'
 import { pipeline } from 'node:stream/promises'
 import * as tar from 'tar'
 import { getImageTotals, listAllImageIndexRows } from '../image-index'
@@ -9,7 +9,7 @@ import {
 } from '../storage-backends'
 import { parseS3Config } from '../storage/s3'
 import { parseTelegramConfig } from '../storage/telegram'
-import { createImageStream } from '../storage'
+import { getBackendForKey } from '../storage/resolver'
 import { copyDatabaseSnapshot } from './db-snapshot'
 import { markJobDone, markJobFailed, updateBackupJob } from './jobs'
 import { BACKUP_FORMAT_VERSION, type BackupManifest, type StorageBackendMetaExport } from './manifest'
@@ -19,6 +19,7 @@ import {
   getBackupsDir
 } from './paths'
 import type { StorageBackendRow } from '../storage/types'
+import { collectMediaAssetKeys } from '../media-assets'
 
 function formatArchiveName(jobId: string): string {
   return `pichost-${jobId}${BACKUP_ARCHIVE_EXT}`
@@ -48,36 +49,15 @@ async function writeStreamToFile(stream: NodeJS.ReadableStream, filePath: string
   await pipeline(stream, createWriteStream(filePath))
 }
 
-async function streamToString(stream: NodeJS.ReadableStream): Promise<string> {
-  const chunks: Buffer[] = []
-  for await (const chunk of stream) {
-    chunks.push(Buffer.from(chunk as Uint8Array))
-  }
-  return Buffer.concat(chunks).toString('utf8')
-}
-
-/**
- * 源文件已按设计删除（转码完成）时，导出 HLS 播放列表、分片与封面。
- * 恢复端会遍历 blobs 目录原样还原，因此这里只需把附属文件写进去。
- */
-async function exportVideoSidecars(row: ImageIndexRow, stagingRoot: string): Promise<void> {
-  const keys: string[] = []
-  if (row.thumb_key) keys.push(row.thumb_key)
-
-  if (row.hls_key) {
-    keys.push(row.hls_key)
-    const dir = row.hls_key.slice(0, row.hls_key.lastIndexOf('/'))
-    const text = await streamToString(await createImageStream(row.hls_key))
-    for (const line of text.split('\n')) {
-      const name = line.trim()
-      if (!name || name.startsWith('#')) continue
-      keys.push(`${dir}/${basename(name)}`)
-    }
-  }
-
+async function exportMediaAssets(
+  row: ImageIndexRow,
+  stagingRoot: string
+): Promise<void> {
+  const backend = await getBackendForKey(row.key)
+  const keys = await collectMediaAssetKeys(row, backend)
   for (const key of keys) {
     await writeStreamToFile(
-      await createImageStream(key),
+      await backend.createStream(key),
       join(stagingRoot, 'blobs', key)
     )
   }
@@ -138,17 +118,10 @@ export async function runFullExportJob(jobId: string, appVersion: string): Promi
     for (const row of rows) {
       updateBackupJob(jobId, {
         progress: processed,
-        message: `正在导出图片 ${processed}/${totals.count + 1}…`
+        message: `正在导出文件 ${processed}/${totals.count + 1}…`
       })
 
-      if (Number(row.source_deleted ?? 0) === 1) {
-        // 转码完成的视频只有 HLS 产物与封面
-        await exportVideoSidecars(row, stagingRoot)
-      } else {
-        const blobPath = join(stagingRoot, 'blobs', row.key)
-        const stream = await createImageStream(row.key)
-        await writeStreamToFile(stream, blobPath)
-      }
+      await exportMediaAssets(row, stagingRoot)
       processed += 1
       updateBackupJob(jobId, { progress: processed })
     }