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/api/videos/upload.post.ts

@@ -10,7 +10,12 @@ import { MAX_FILES_PER_UPLOAD } from '../../utils/constants'
 import { createApiError } from '../../utils/api-error'
 import { checkUploadRateLimit } from '../../utils/rate-limit'
 import { processSingleVideoUpload } from '../../utils/file-bed'
-import { enqueueTranscode } from '../../utils/transcode'
+import {
+  enqueueTranscode,
+  MAX_TRANSCODE_BITRATE_PERCENT,
+  MIN_TRANSCODE_BITRATE_PERCENT,
+  parseTranscodePreset
+} from '../../utils/transcode'
 import { getFileBedAccessMode } from '../../utils/env'
 
 export default defineEventHandler(async (event) => {
@@ -37,6 +42,36 @@ export default defineEventHandler(async (event) => {
       )
     : false
 
+  const presetField = formData.find(part => part.name === 'transcodePreset')
+  const presetRaw = presetField?.data?.length
+    ? new TextDecoder().decode(presetField.data).trim()
+    : ''
+  const transcodePreset = presetRaw ? parseTranscodePreset(presetRaw) : undefined
+  if (presetRaw && !transcodePreset) {
+    createApiError(event, 'INVALID_REQUEST', '无效的转码质量档位', 400)
+  }
+
+  const bitrateField = formData.find(part => part.name === 'transcodeBitratePercent')
+  const bitrateRaw = bitrateField?.data?.length
+    ? new TextDecoder().decode(bitrateField.data).trim()
+    : ''
+  const transcodeBitratePercent = bitrateRaw ? Number(bitrateRaw) : undefined
+  if (
+    bitrateRaw
+    && (
+      !Number.isInteger(transcodeBitratePercent)
+      || transcodeBitratePercent! < MIN_TRANSCODE_BITRATE_PERCENT
+      || transcodeBitratePercent! > MAX_TRANSCODE_BITRATE_PERCENT
+    )
+  ) {
+    createApiError(
+      event,
+      'INVALID_REQUEST',
+      `转码目标码率需为 ${MIN_TRANSCODE_BITRATE_PERCENT}–${MAX_TRANSCODE_BITRATE_PERCENT} 的整数`,
+      400
+    )
+  }
+
   const fileParts = formData.filter(
     part => (part.name === 'file' || part.name === 'files' || part.name === 'video')
       && part.data?.length
@@ -82,7 +117,10 @@ export default defineEventHandler(async (event) => {
 
   if (wantTranscode) {
     for (const item of items) {
-      enqueueTranscode(item.key)
+      enqueueTranscode(item.key, {
+        ...(transcodePreset ? { preset: transcodePreset } : {}),
+        ...(transcodeBitratePercent !== undefined ? { bitratePercent: transcodeBitratePercent } : {})
+      })
     }
   }