[WIP] [ISSUE-3] Fix inconsistent child indication logic

[Claude]

Thanks for assigning this issue to me. I'm starting to work on it and will keep this PR's description up to date as I form a plan and make progress.

Original prompt

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This section details on the original issue you should resolve

<issue_title>Which way to indicate child? isChild or child?</issue_title>
<issue_description>There's two way to indicate a passenger is a children,

in Air/Services/transformer/add-meta-passengers-booking.js

      item.isChild = true;

in Air/Services/transformer/convert-passengers-object-to-array.js

          child: (ageCategory === 'CNN'), // quickfix

This makes really confusing, to them or to implement other features. Can you sort them out? </issue_description>

Comments on the Issue (you are @claude[agent] in this section)

• Fixes Which way to indicate child? isChild or child? #428

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

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