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

app/components/ClearStorageModal.vue

@@ -0,0 +1,159 @@
+<script setup lang="ts">
+const props = defineProps<{
+  open: boolean
+}>()
+
+const emit = defineEmits<{
+  'update:open': [value: boolean]
+  'cleared': []
+}>()
+
+const { t } = useI18n()
+const toast = useToast()
+const step = ref<'warning' | 'confirm'>('warning')
+const confirmation = ref('')
+const clearing = ref(false)
+
+const canConfirm = computed(() =>
+  !clearing.value && confirmation.value.trim() === t('storage.clearStoragePhrase')
+)
+
+watch(() => props.open, (open) => {
+  if (open) {
+    step.value = 'warning'
+    confirmation.value = ''
+    clearing.value = false
+  }
+})
+
+function close() {
+  if (clearing.value) return
+  emit('update:open', false)
+}
+
+function goToConfirm() {
+  step.value = 'confirm'
+}
+
+function clearBrowserCache() {
+  const keys = [
+    'pichost.upload-preferences',
+    'pichost.upload-preferences.video',
+    'pichost.upload-preferences.file',
+    'pichost.recent-tag-ids',
+    'pichost.library-view.image',
+    'pichost.library-view.video',
+    'pichost.library-view.file'
+  ]
+  for (const key of keys) localStorage.removeItem(key)
+}
+
+async function confirmClear() {
+  if (!canConfirm.value) return
+  clearing.value = true
+  try {
+    const result = await $fetch<{
+      deletedMedia: number
+      deletedObjects: number
+      clearedCacheDirs: number
+      failed: Array<{ key: string }>
+    }>('/api/user/storage/purge', {
+      method: 'POST',
+      credentials: 'include',
+      body: { confirmation: confirmation.value.trim() }
+    })
+
+    clearBrowserCache()
+    emit('cleared')
+
+    if (result.failed.length) {
+      toast.add({
+        title: t('storage.clearStoragePartial', {
+          failed: result.failed.length,
+          total: result.deletedMedia + result.failed.length
+        }),
+        color: 'warning'
+      })
+    } else {
+      toast.add({
+        title: t('storage.clearStorageSuccess', {
+          files: result.deletedObjects,
+          cache: result.clearedCacheDirs
+        }),
+        color: 'success'
+      })
+    }
+    emit('update:open', false)
+  } catch (error: unknown) {
+    const message = error && typeof error === 'object' && 'data' in error
+      ? (error as { data?: { error?: { message?: string } } }).data?.error?.message
+      : undefined
+    toast.add({
+      title: message || t('storage.clearStorageFailed'),
+      color: 'error'
+    })
+  } finally {
+    clearing.value = false
+  }
+}
+</script>
+
+<template>
+  <UModal
+    :open="open"
+    :title="step === 'warning' ? t('storage.clearStorageTitle') : t('storage.clearStorageFinalTitle')"
+    @update:open="emit('update:open', $event)"
+  >
+    <template #body>
+      <template v-if="step === 'warning'">
+        <UAlert
+          color="error"
+          variant="subtle"
+          icon="i-lucide-octagon-alert"
+          :description="t('storage.clearStorageWarning')"
+        />
+        <p class="mt-3 text-sm text-muted">
+          {{ t('storage.clearStorageScope') }}
+        </p>
+      </template>
+
+      <template v-else>
+        <p class="text-sm leading-6 text-muted">
+          {{ t('storage.clearStorageInstruction') }}
+        </p>
+        <UInput
+          v-model="confirmation"
+          class="mt-3 w-full"
+          :placeholder="t('storage.clearStoragePlaceholder')"
+          autofocus
+        />
+      </template>
+    </template>
+
+    <template #footer>
+      <div class="flex w-full justify-end gap-2">
+        <UButton
+          :label="t('common.cancel')"
+          color="neutral"
+          variant="outline"
+          :disabled="clearing"
+          @click="close"
+        />
+        <UButton
+          v-if="step === 'warning'"
+          :label="t('common.continue')"
+          color="error"
+          @click="goToConfirm"
+        />
+        <UButton
+          v-else
+          :label="t('storage.clearStorageConfirm')"
+          color="error"
+          :loading="clearing"
+          :disabled="!canConfirm"
+          @click="confirmClear"
+        />
+      </div>
+    </template>
+  </UModal>
+</template>