Add ability to create custom fields (non-RFS) during content type migration

[dominikag2]

Motivation

While working with our partner Wakefly, we identified a common pattern where widgets utilize collections in KX13, and preserving the widget-collection relationship during migration is crucial for the editor experience.

When we discussed content remodeling options—specifically, adding a taxonomy field to preserve this relationship—they were very enthusiastic. They indicated this would be their preferred approach from the editor's experience perspective and want to use it for most of their widgets following this pattern. This approach has been validated from a content modeling perspective and represents a sound architectural solution.

This is not an isolated use case - many partners and clients use similar content models in KX13 to what Wakefly has implemented.

Current Workarounds Are Insufficient
Custom Class Mapping: Not suitable because you must specify ALL fields, not just the new one.

Manual Approach: Run migration → manually add fields via XbyK admin → replace --page-types with --bypass-dependency-check → rerun migration. This is manual, error-prone, doesn't scale, interrupts workflow, and is hard to version control.

Custom Code in Program.cs: Too "hacky" (especially for a common use case), non-trivial and looks bad that we don't support a simple adding a field scenario out of the box.

We need an officially supported solution that enables best-practice content modeling during migration without hacky workarounds or manual processes.

Proposed solution

The ability to add custom fields to a content type during data migration (whether taxonomy or other field types). Eother during class mapping or any other better suited spot - open to your suggestion.

Additional context

Use Case Example: Wakefly's widgets reference collections in KX13. Adding a taxonomy field during migration preserves this relationship while maintaining semantic meaning and providing an good editor experience.

@brittanysan4d and I (@dominikag2 ) would love to answer any questions if necessary and collaborate on making this happen.