Trig recipe cleanup

[ajpal]

1. Add panic! if run_rule_lifting doesn't find rules
2. Restructure the trig recipe so that each phase is self-contained. I think it's easier to tell what's in each workload if there's fewer layers of plugs, and everything is local in the file. Lmk what you think!

The workloads + rules are very similar, but not identical. The new rules can derive 100% of the old rules, though, so hopefully it should be okay.