Add custom fields to KiCad interface to support KiCost

[Kampi]

Describe the solution you'd like

When using the KiCost plugin (i.e., with KiBot), you need the fields manf, manf#, and distributor-specific fields like mouser# to add the manufacturer, the part number, and the order number for the part. KiCost parses these fields to get the costs for specific components. The result looks like this.

I want to combine KiCost with the components from the KiCad interface, so either there must be a way to add custom fields to the interface, or the existing fields must be changed.