fix(amazonq): file opening behavior on accepted changes

[kelvin-klchu]

Problem

• when you accept an individual code change, it will bring up the file window
• when you update the accepted file, both left and right of the window reflects the changes you made immediately
• it should only show the changes made on the left, while the right stays the same as the original suggested code change

Solution

• updated the way vscode.diff is called when opening up the file such that it is the actual file on the left, and the suggested code change stays on the right

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

[github-actions]

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  • 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.

[jpinkney-aws]

I'll wait for approval from your team before merging