Thank you very much for making these changes, and so quickly. Everything looks great (nice fix in afw), though I did want to make one suggestion about a pre-existing issue in meas_base.
From the documentation of ForcedMeasurementTask it sounds as if most users that call generateSources will then immediately have to call attachTransformedFootprints (which will be overridden if needed). If so, this sounds a bit clumsy to me. I suggest you have generateSources peform that call, with a boolean flag to disable if necessary. Or if the decision to call attachTransformedFootprints is intrinsic to the task, then make subtasks override generateSources. If you do make this change then is it also reasonable to make attachTransformedFootprints private (by prefixing an underscore)?
Thank you very much for the extra note on documentation for the measCat argument of ForcedMeasurementTask.run about using generateSources. I was hoping you add that.