fix(amazonq): Q infers source file from active test file for UTG.

[laileni-aws]

Problem

• If user tries to run /test on the test file, Q considers test file as source file and starts the test generation on the test file.

Solution

• If user tries to run /test on the test file, Q infers the context from the original source file and generate tests accordingly.
• No change in functionality, minor change in UX filename.

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[github-actions]

• This pull request modifies code in src/* but no tests were added/updated.
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