Reduce use of Board for serialization

[Chris-Hibbert]

What is the Problem Being Solved?

The way we use marshalers from the board is wasteful. We send more data than necessary.

Description of the Design

We could change the contracts to use a local wrapper of the marshaller to send only slot values. Another possibility is to add caching.

Security Considerations

Not a security issue.

Scaling Considerations

The goal is to address scaling/performance issues.

Test Plan

straightforward

Upgrade Considerations

If we build something, it can be deployed one contract at a time.