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
I guess this falls in the premature optimization that we have discussed in
previous PRs as in general this is simply a loop within the raw data that
we have that in general should always be < 5 and perhaps in the future <
10.