Title: Device login fails: ENOTFOUND next-waitlist.azurewebsites.net

### Describe the bug

When running `github-copilot-cli auth login`, the device code flow starts normally.
I enter the code at https://github.com/login/device and approve access.

After approval, the CLI fails with:

Failed to authenticate: getaddrinfo ENOTFOUND next-waitlist.azurewebsites.net, undefined

The domain next-waitlist.azurewebsites.net does not resolve (NXDOMAIN).

Environment:
- WSL2 (Ubuntu)
- Node v20.19.3
- npm v11.7.0
- github-copilot-cli v0.1.36

This appears to be a regression in the latest CLI version.

### Affected version

_No response_

### Steps to reproduce the behavior

_No response_

### Expected behavior

_No response_

### Additional context

_No response_