feat(amazonq): initialize feature branch with gamma endpoint.

[Hweinstock]

Problem

There is currently no way to test gamma changes without manually overriding the endpoint.

Solution

• create a feature branch that points to gamma so that we can easily test in pre-prod.

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• Treat all work as PUBLIC. Private feature/x branches will not be squash-merged at release time.
• Your code changes must meet the guidelines in CONTRIBUTING.md.
• 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.
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