feat: 支持辅助栏背景设置

[suiyun39]

Checklist - zh-CN

• 阅读 贡献指南。
• 把 issue 和 pr 相关联.
• 确保代码与 master 分支保持同步.
• 尽可能详细的描述所做的变更.

内容摘要

为辅助栏（右侧边栏）增加了背景设置支持，具体效果如下：

[Copilot]

Pull Request Overview

This PR adds support for configuring background images for the auxiliary bar. Key changes include:

• Adding new configuration and integration for the auxiliary bar via AuxiliarybarPatchGenerator in PatchGenerator/index.ts.
• Introducing a new module (PatchGenerator.auxiliarybar.ts) that extends the fullscreen patch generator for auxiliary bar styling.
• Updating configuration schemas and documentation (nls files, package.json, and README files) to include auxiliary bar settings.

Reviewed Changes

Copilot reviewed 9 out of 9 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
src/background/PatchGenerator/index.ts	Added import and integration of AuxiliarybarPatchGenerator.
src/background/PatchGenerator/PatchGenerator.auxiliarybar.ts	Created the auxiliary bar patch generator module.
package.nls.zh.json, package.nls.json, package.nls.ja.json	Added auxiliarybar description messages for localization.
package.json	Defined auxiliarybar configuration schema.
README.zh-CN.md, README.md, README.ja-JP.md	Updated documentation to include auxiliarybar feature details.

Comments suppressed due to low confidence (1)

src/background/PatchGenerator/index.ts:30

• Consider adding explicit unit tests for the auxiliarybar background generation to ensure consistent behavior with the other sections.

new AuxiliarybarPatchGenerator(options.auxiliarybar).create(), // auxiliarybar