Can not loggin with the Enterprise subcription

Hi team,
Im trying to use the copilot with my enterprise account. but it seems not able to authenticate.

When I tried to do the `Copilot setup` as instructed, the following message shown to me:
```bash
[2025-11-04 15:16:17] [ERROR] Method workspace/executeCommand errored with E1001: "FetchError: self-signed certificate in certificate chain"
```

I checked with the admin team, they confirmed there is not any firewall which might block this.

additionally I could successfully log in in VS Code/Android Studio Github Copilot with the same account.

Thanks.

issue 中沒有指定原始檔案或測試。先使用企業帳戶在 Neovim 中重現 `Copilot setup`，並追蹤包含自簽章憑證錯誤的 `workspace/executeCommand` 失敗。企業帳戶能夠在沒有 E1001 的情況下成功驗證身分，即表示完成。

由索引模型根據 Issue 內容生成。