Reduce chain state growth rate

[orriin]

Need to investigate which keys are mostly responsible for the growth in the last 6 months, and suggest how to slow it.

AC:

• [ ] identify the top storages contributing to state growth
• [ ] if there is no-longer-needed or redundant data we can prune, identify that
• [ ] write migrations removing prunable data, if applicable
• [ ] more exotic things like storage compression...?