[产品讨论] PR #887 feat(desktop): 增加宿主受控的插件皮肤

## 触发原因

PR #887 新增宿主受控的插件皮肤系统，属于新增产品能力。

## 需要确认

- 插件皮肤的产品定位与适用范围？
- 宿主受控的边界与插件作者的自由度？

## 放行方式

产品白名单成员（@dashhuang / @xdanger / @MagicLizi / @zqchris）在本 issue 或 PR 评论区明确同意。

---
关联 PR:#887(作者 @maoxinxin-xd);本 issue 由 review-pr 流程自动创建,用于先讨论该 PR 涉及的产品 / UI 变更,聊清楚后 PR 会恢复审查。

Start by reading PR #887 and the product questions in this issue. Clarify the plugin skin's product scope, the host-control boundary, and plugin-author freedom; the work is done when an approved product decision is recorded by a whitelist member in this issue or the PR comments.

Written by the indexing model from the issue text.