This is best explained by your counselor in their letter, saying something about your overall consistent excellent academic achievement having been only very briefly affected by your having lost 12 family members - cousins and their families - in a war bombing in the fall of '24. The counselor should emphasize that the shock of learning of this extended family tragedy only briefly affected your academic performance, and that you quickly recovered, getting a 97% on the Calc final, and if she can point to recovery in AP Research, she should mention that too. The goal is to portray you as demonstrating resilience - which you clearly did. If it is too late by the time you get back to school, you could ask the counselor to send an addendum to the schools with this info - I think it is certainly warranted, and it would get there in time to be added to your file before review.
You should not include this in your own additional info section at all, and most definitely not with a description of the status of those killed, where, by whom, in what manner, and for what reason. First of all, it’s always better if any explanation of hardships comes from the counselor, rather than from you. It validates the adverse circumstances, and avoids any semblance of appearance of your making an excuse for a drop in grades. The counselor should not even mention which war - of course, by your name, the school may realize that it’s in the middle east, but similar tragedies are ongoing in other areas of the world, too - and the point is the loss of extended family members, and its effect on you, not the political argument behind it.
Political protests on campus about the war in the Middle East have been a huge problem for college administrations. Admissions officers with 20 qualified applicants for every seat could easily decide to put yours aside, not out of prejudice but out of a vague concern that you could be more likely to join the protests, which have been very disruptive on many campuses. No one in the admissions committee will say this directly, but there are so many reasons to take another qualified applicant over you, without anyone saying a word about on-campus protests against Israel.
You have a really strong academic record, and stellar SAT scores. You’ve got a very interesting EC with intense involvement and leadership. As long as the admissions committees are made aware by your counselor of the circumstances, I don’t think that they will hold that brief drop in grades against you.
The bigger issue is that you have only listed extreme reaches, no matches or safeties. And I think you said that you were going to high school in the US, but did not mention whether or not you were applying as an international student (without a US green card or US citizenship). If that is the case, it could make your odds of acceptance even lower.