Improve AMIP and coupler conservation tracking

[juliasloan25]

It would be nice to be able to track conservation in our AMIP runs, especially given the discrepancies in conservation we've seen between CPU and GPU runs for slabplanet. We should add a feature to keep track of the fluxes throughout AMIP simulations so we can look at energy and water conservation.

cc @LenkaNovak

Relevant issues:

• Reduce conservation error (currently larger than sqrt(eps)):
  • Include sublimation
  • Investigate CPU conservation degradation at radiation dt