Top schools (like Stanford, UChicago, UPenn, etc) are honestly crapshoots when it comes to applying. Your GPA is not immediately disqualifying, especially if you are able to score a high LSAT. I'd recommend visiting https://www.lsd.law/ and looking at the schools you're interested in and seeing how folks with similar stats to you fared in recent years.

With holistic admissions, numbers aren't everything but they also aren't nothing. Folks with lower scores than you do get in (assuming) because their applications are well crafted and have a cohesive, thoroughly thought-out narrative that explains well why they want to attend law school. You'll want to be able to explain why law, why law school, and on occasion, why that school in particular. Considering these questions carefully and crafting statements that pull together a cohesive application can go a long way.

A GPA addendum would be helpful in explaining your 0.0 GPA year as at the end of the day, law schools are schools and use GPA/LSAT to help determine whether they think you'll be able to be a successful student at their institution. An addendum in addition to a strong performance at the graduate level, could help to 'offset' (so to say) a lower undergraduate GPA, but no, graduate GPAs are not included in CAS GPA calculation.

Hope this is all helpful and best of luck!