WIP: New split lib workflow

We need to:
- [ ] check that meta-analysis is still working
- [ ] finish preprocessing (split libs) connect per prep template
- [ ] make preprocessing async
- [ ] be able to connect to other studies raw data
- [ ] fix metadata summary per prep template
- [ ] add EBI submission
Okay, thanks. The comment didn't indicate those steps were blocking this PR specifically, but rather that they might have been things remaining to do once the PR was merged.