Given the height of the plant and "tidy" nature of the snipped-off branch tips, a rabbit is a more likely culprit than deer, though deer could browse on redbuds as well. Deer tend to tear off what they bite (because they don't have upper front teeth), whereas rabbits create pruner-like cuts, often at around a 45-degree angle.

It might be a bit early to judge if the now-bare branches/stem will leaf-out again. The fact that damage occurred about a month ago would normally suggest that no new growth this much after the fact means that the bare wood is dead or too weakened to recover, but the complicating factor may be the overnight freeze we experienced last week, which damaged or killed the new growth on many species of trees and shrubs. As such, you might want to give the young plant another couple of weeks or so to determine if it's able to leaf-out again or not. If it doesn't, trim back that bare wood, and hopefully the new growth that did emerge will gradually replace what was lost.

In the meantime, you can also monitor it for watering needs, since the ongoing drought is stressing many plants and producing new growth relies on readily-available root moisture.

Miri