202: Remove `Hash` for ID types r=kvark a=grovesNL
Reverts some of the `Hash` derives added in #200 because we don't have a good way to support `Hash` for JavaScript objects (for the web backend) at the moment. JavaScript objects don't have a unique identifier that we can use for `Hash`, so any solution here would probably mean adding our own map of JS object<->unique ID.
Co-authored-by: Joshua Groves <josh@joshgroves.com>