[Doc] No document related to enterprise policy enforcement for local sandbox

### Describe the bug

In sandbox document, there is only a description that local sandbox can be managed by Microsoft Intune or MDM, however, there is no detailed information about how enterprise user can config and use it:

> [Enterprise policy enforcement](https://docs.github.com/en/copilot/concepts/about-cloud-and-local-sandboxes?search-overlay-input=detailed+information+about+%3A+Enterprise+policy+enforcement+For+organizations+and+enterprises%2C+local+sandbox+policies+can+be+centrally+configured+and+enforced+using+Microsoft+Intune+and+other+MDM+%28mobile+device+management%29+platforms.+This+gives+administrators+control+over+how+Copilot+interacts+with+local+resources+across+managed+devices.&search-overlay-ask-ai=true#enterprise-policy-enforcement)
For organizations and enterprises, local sandbox policies can be centrally configured and enforced using Microsoft Intune and other MDM (mobile device management) platforms. This gives administrators control over how Copilot interacts with local resources across managed devices.

### Affected version

_No response_

### Steps to reproduce the behavior

_No response_

### Expected behavior

_No response_

### Additional context

_No response_

从链接的 about-cloud-and-local-sandboxes 文档开始，检查 Enterprise policy enforcement 部分。记录企业用户如何通过 Microsoft Intune 和其他 MDM 平台配置和使用本地沙盒策略；当页面提供超出现有概览的详细配置和使用指导时，即表示完成。

由索引模型根据 Issue 内容生成。