Check assertions after the fact

The issue I reported in https://github.com/JuliaLang/julia/issues/35601 throws an assertion on a debug build. It should be possible for us to compile a version of julia that has assertion disabled, but lets us run the assertions at replay time to see if any of them fail.

Start by reading JuliaLang/julia issue 35601 and inspecting the BugReporting.jl entry points related to assertion handling. The payload names no files or tests, so first map how debug-build assertions and replay work. Done means a Julia build can disable assertions during compilation while checking them during replay.

Written by the indexing model from the issue text.