feat(generator): Added mapping of additional Tezos types.

feat(generator): Added mapping of additional Tezos types:

• bls12_381_fr -> string.
• bls12_381_g1 -> string.
• bls12_381_g2 -> string.
• chest -> string.
• chest_key -> string.
• constant -> Always throws because it should be expanded upfront.
• never -> never.
• sapling_state -> string.