* feat: `Nova` can be serialized and deserialized

* chore: (temp) allow dead code as serde is not yet used

* fix: require trait in `where` to not increase restrictions on
`CommitmentScheme`

* feat: add file with nova serialization methods

* fix: change call to get poseidon config and chore: update traits for serde

* chore: remove clang install from CI, move tests and remove unnecessary
allow

* feat: remove serializing r1cs and cs params and provide them at
deserialization time

* chore: initialize r1cs within deserialization function directly