vouch request for #3292 #4347

Why do you want to contribute?

hey, want to pick up #3292, the nanosecond timestamp thing in eventRepository. issue already spells out the fix pretty well, theres a helper called convertDateToNanoseconds() in the same file thats doing the BigInt conversion the right way (BigInt first then multiply) so i just need to make the other functions do the same instead of multiplying before casting. issue mentions 4 spots total, 2 shown directly in the description and 2 more named in other files. gonna add tests too. can look at other stuff after if theres more thats needed

Prior contributions or relevant experience

No response