Amazon Q authentication fails on VS Code 1.118.1 on Windows, but works after downgrading to VS Code 1.109.0

## Summary

Amazon Q authentication does not complete on VS Code 1.118.1 on Windows.

The extension gets stuck during authentication and never creates a valid connection. After downgrading VS Code to 1.109.0, using the same Amazon Q extension version and the same AWS account, authentication works correctly.

This suggests a compatibility issue between newer VS Code versions and the Amazon Q authentication flow on Windows.

---

## Environment where it fails

- OS: Windows
- VS Code version: 1.118.1
- Amazon Q extension version: 2.0.0
- AWS Toolkit extension: tested both installed and not installed
- Authentication type: IAM Identity Center / Company account
- Browser: Microsoft Edge
- Network: no proxy configured
- AWS config: tested with and without `.aws/config`
- Regions tested: `sa-east-1` and `us-east-1`

---

## Environment where it works

- OS: Windows
- VS Code version: 1.109.0
- Amazon Q extension version: 2.0.0
- AWS Toolkit extension: not installed
- Same AWS account
- Same IAM Identity Center Start URL
- Same authentication flow

After downgrading from VS Code 1.118.1 to VS Code 1.109.0, Amazon Q authentication started working again.

---

## Symptoms

On VS Code 1.118.1:

- Amazon Q gets stuck during authentication.
- Sometimes the UI shows `Authenticating in browser...`.
- AWS/Amazon Q connection is never created.
- `AWS: Add New Connection` / connection-related commands either do nothing or do not complete.
- Amazon Q logs repeatedly show `No connection found` and `PENDING_CONNECTION`.

---

## Relevant log excerpts

```txt
connection isValid=false
connection isValidCodewhispererCoreConnection=false
connection isExpired=false
secondaryAuth isExpired=false
connection isUndefined=true

No source file or test is named. Start by reproducing the authentication flow on Windows with VS Code 1.118.1 and 1.109.0, then inspect the Amazon Q logs around PENDING_CONNECTION, No connection found, and the connection commands. Done means IAM Identity Center authentication completes and creates a valid connection on the newer VS Code version.

Written by the indexing model from the issue text.