[Refactor] Isolate a synthesizer-error crate

[ljedrz]

This PR facilitates concrete error use in crates which would otherwise run into circular dependencies (e.g. #3101).

The only "internal" dependencies of the new crate are circuit-environment and console-network, and they should remain minimal to ensure broad applicability.

[vicsn]

@raychu86 is your release process robust against new crates? I recall it skipped over a new one once.

[raychu86]

The release process needs to be updated manually if there are new scripts. I had intended to add automated checks, but never got around to it since crate additions are fairly rare.

[mitchmindtree]

Apologies for the delay, LGTM