My toddler does everything she can to resist sleep.

Be patient but firm. Toddlers want independence when it suits them but demand you remain close & nurturing.This extends to bedtime when previously good sleepers may become anxious about separation.I encourage a calming night ritual followed by tucking the child in.Require that the child remain in his/her room until morning.Reward him/her with an open door if so, closed if not & return every time if venturing out.
Most of what she... ...Does, she does to get your attention. Remove yourself, and you remove her incentive to keep herself awake. Very few great actors put on a show if there is no audience, and very few toddlers avoid being great actors.