fix(auth): prevent concurrent token refresh and adding necessary logs

[laileni-aws]

Problem

• There was a significant increase in call volume for the sso-oidc CreateToken operation from AmazonQ-For-VSCode clients.

Solution

• The root cause was identified as a race condition in concurrent asynchronous token refresh operations within the VSCode extension. When bearer tokens expired (after 1 hour), multiple simultaneous calls to getToken() independently triggered token refresh operations, resulting in duplicate OIDC API calls.
• Implemented a "promise deduplication" pattern to prevent duplicate async OIDC calls.

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[github-actions]

• This pull request modifies code in src/* but no tests were added/updated.
  • Confirm whether tests should be added or ensure the PR description explains why tests are not required.
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[Will-ShaoHua]

nit: let's add a topic for this logger

[rli]

please follow up with test if possible