[UM] Practice option to set active card cooldowns

[Guy-L]

Hi, first of all - very appreciative of all the nice convenience features that have been added to thprac for UM. This one may be a big ask, and I'm kicking myself for not requesting it sooner. I'd like it to be possible to set the cooldown% of the currently equipped Active cards in the thprac practice menu, similar to how the trance% is changeable in TD. This would tremendously help with practice for all scoring categories.