fix(dev): Q dev handle no change required

[chengoramazon]

Problem

• Q dev won't be able to generate code for unrelated prompts. (e.g. explain the code)
• It would be a bad CX if Q fail to generate code without guiding users the proper use cases.

Solution

• Handle no code change required explicitly.
• Allow users to provide more details

res.mov

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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.

[osdemah]

LGTM

[justinmk3]

Thanks for including a changelog. Please review the changelog guidelines. This doesn't meet those guidelines.