Signature lighting is the upper and lower white strip that is dimly lit during the day when the headlights are not on. Some people refer to them as “halos” (I have no clue why, because they are not rings around projectors). These are a completely different feature than DRLs. You have the turn signals set as DRLs, which are only powered on during the day when the headlights are off. When the headlights come on, the DRL circuit switches off (because they are not needed anymore), hence the reason they change into their normal white parking lights. There’s no way for them to behave like you are wanting them to without doing some wiring with some diodes.