Add attestation validators for know attestation types

[bitbeckers]

Describe the feature you'd like to request

To make sure a created attestation contains data that we can support, add a Validator class for attestation.

Describe the solution you'd like

The validator should not only check on the schema, but also fields like chainID, contractAddress, and tokenID.

• chainID should be supported
• contractAddress should be known
• tokenID should be a valid hypercert claim tokenID (e.g. the baseType tokenID not a fraction instance)

Describe alternatives you've considered

Yooloing data but that appears to break the API as reported in hypercerts-org/hypercerts-indexer#253