Authenticates but never getting to a prompt in the chat window (progress bar keeps spinning)

## Problem
I have a VS code setup that worked pretty well. A Couple of days ago I had to input again the start url and select the region. The authentication seems to be working but the Amazon Q icon in the side bar has a clock over it.

## Steps to reproduce the issue

1. In VS with the Amazon Q extension installed
2. Click on Amazon Q in the lower status bar and then select the Authenticate option in the commands list at the top.
3. Allow access in the page in the browser and it authenticates
4. Click on the Amazon Q icon in the side bar. The progress bar at the top keeps on forever and never get the prompt.

## Expected behavior
I should get the prompt where I can ask questions.

## System details (run `AWS: About` and/or `Amazon Q: About`)

- OS: Windows 11
- Visual Studio Code version: 1.99.2
- AWS Toolkit version:
- Amazon Q version: 1.65.0

Start by reproducing the issue in the Amazon Q VS Code extension using the listed authentication steps on Windows 11 with VS Code 1.99.2 and Amazon Q 1.65.0. Trace the authentication-to-chat flow and confirm that the Amazon Q sidebar reaches a usable prompt instead of spinning indefinitely.

Written by the indexing model from the issue text.