feat: add download feature for attachment (#5496)

#### What type of PR is this?

/kind feature
/area ui
/milestone 2.14.0

#### What this PR does / why we need it:

附件支持下载。

<img width="471" alt="image" src="https://github.com/halo-dev/halo/assets/21301288/97909ef8-8117-4ea9-aa15-73295a1b7b01">


#### Which issue(s) this PR fixes:

Fixes #5476

#### Special notes for your reviewer:

测试方式：

1. 上传若干附件。
2. 测试下载功能是否符合预期。

#### Does this PR introduce a user-facing change?

```release-note
为附件添加下载功能
```

ui/console-src/modules/contents/attachments/components/AttachmentListItem.vue

@@ -7,6 +7,7 @@ import {
  Toast,
  VDropdownItem,
  Dialog,
+ VDropdownDivider,
 } from "@halo-dev/components";
 import { computed, ref } from "vue";
 import type { Attachment } from "@halo-dev/api-client";
@@ -101,6 +102,29 @@ const { operationItems } = useOperationItemExtensionPoint<Attachment>(
  {
  priority: 20,
  component: markRaw(VDropdownItem),
+ label: t("core.common.buttons.download"),
+ action: () => {
+ const { permalink } = attachment.value.status || {};
+
+ if (!permalink) {
+ throw new Error("Attachment has no permalink");
+ }
+
+ const a = document.createElement("a");
+ a.href = permalink;
+ a.download = attachment.value.spec.displayName || "unknown";
+ document.body.appendChild(a);
+ a.click();
+ document.body.removeChild(a);
+ },
+ },
+ {
+ priority: 30,
+ component: markRaw(VDropdownDivider),
+ },
+ {
+ priority: 40,
+ component: markRaw(VDropdownItem),
  props: {
  type: "danger",
  },