Request stack trace at point of execution without throwing exceptions

[borkdude]

As a follow up to #774, it has come up that users want to request a stack trace at the point of execution, just for debugging / printing. To facilitate this we should pre-process the stack instead of constructing during an exception such that you have it readily available.

You can see the beginnings of it in this case: (try (/ 1 0) (catch ^:sci/error Exception e)) where the error has one stack element about / but none of the preceding ones, which we can add during analysis time.