Allow promotion per category of products
Originally, the list of products is limited to product with the same category of UoM as the one on the promotion. But indeed this limitation is not really necessary and also avoid the usage of this list as filter for promotion without quantity limitation.
So I think we should remove the UoM constraint and let just the user dealing with a contradicting configuration (ex: set a UoM and any products of this UoM).
If we do this change, we can add also a list of categories to limit the application of the promotion.