fix(amazonq): make code fix's line number or file to be accurate

[zuoyaofu]

Problem

1. document.lineAt would error due to line out of bounds.
2. File uploaded for codeFix is not the same as the one in editor

Solution

1. Remove document.lineAt logic
2. Ensure dirty file is saved before zipping.

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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.
  • Confirm whether tests should be added or ensure the PR description explains why tests are not required.

[justinmk3]

Can this wait until next week's release?

[zuoyaofu]

Can this wait until next week's release?

Yes, this is not as urgent.