Sync API Refactor

[helmturner]

PR Checklist

• [ ] Addresses an existing open issue: fixes #000
• [ ] That issue was marked as status: accepting prs
• [ ] Steps in CONTRIBUTING.md were taken

Overview

Refactor sync api to be easier to follow and map nicely with the new async api (wip)

• use maps/sets for more declarative code
• rename things Change the api for guards to be separate from that of serialize/deserialize type handlers
• give guards their own configuration, but still run them for any unhandled values