Add multihit model in a few more places

make format

fix shape issue

fix rebase issue, but tests still fail

force_spawn in tests

reformat

switch to serial branch length optimization

multihit works with threading

WIP-- nothing works now

comment

test+fake multihit working

re-enable multihit

perhaps working, fixed device mismatch and switched to nonlog correction application

I think this might have worked

verified working here

cleanup for PR