Invoice Format for intercompany invoices - add additional details

Summary:

We create project costs (non-labor) and then bill them on intercompany project invoices.

At the contract level > bill plan > invoice format is set for internal invoices, with grouping option as Contract Line.

In the invoice format details, we use the attribute name = contract line, which is fine.

Business requirement is to add on the invoice line description also additional details from the project costs, which is stored in a DFF.

Requirement is similar to How To Default DFF's Entered In Event To Contract Line And Transfer To AR (KB24195)

The DFF value contains the period for which cost was generated (eg. Jan-25, Feb-25).