fix(amazonq): add throttling exception handling and in code comments for featureDev quota

[willyyhuang]

Problem

Follow up of #6091

Solution

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License: I confirm that my contribution is made under the terms of the Apache 2.0 license.

[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.
• This pull request implements a feat or fix, so it must include a changelog entry (unless the fix is for an unreleased feature). Review the changelog guidelines.
  • Note: beta or "experiment" features that have active users should announce fixes in the changelog.
  • If this is not a feature or fix, use an appropriate type from the title guidelines. For example, telemetry-only changes should use the telemetry type.

[willyyhuang]

Not adding any change log due to this being the same change from the previous PR mentioned, but just added some in code comments & refactoring code