Refactor cluster definition and lock fields to hex

[corverroos]

Problem to be solved

We currently use golang/json package's default formatting of bytes in our cluster definition and cluster lock json objects which is base64 standard.

This is causing problems for DV-launchpad as it uses the definition config hash for routing to its backend and base64 standard isn't URL safe.

Proposed solution

The following formats are available to choose from:

• hex: We leave hex for "eth2" things like group pubkey and ENRs. We want to use a different format for charon/obol specific things so users are less easily confused. Like thining the DV pubkey is one of the pubshares since those would also look like addresses.
• base64 URL: base64 URL addresses the problem of using base64 in URLs be replacing "/" with "_" and "+" with "-". This could work but the resulting encoding still contain "special characters" which can be hard to work and look at for humans.
• base58: base58 is both URL safe and human friendly. It only contains alpha numeric characters exluding look-alikes like "I" and "l". Base58 is also a common format in other crypto currencies, but not ETH (yet).

Final proposal:

• We therefore suggest refactoring all byte fields from base64 standard to )x prefixed hex since that is the Ethereum standard which simplifies the config and aligns it with our industry.
• These fields include:
  • cluster-definition.config_hash
  • cluster-definition.definition_hash
  • cluster-definition.operators.config_signature
  • cluster-definition.operators.enr_signature
  • cluster-lock.lock_hash
  • cluster-lock.signature_aggregate
  • cluster-lock.distributed_validators.public_shares
• Increase the version from 1.1.0 to 1.2.0.
• Since this is only cosmetic (the data is unchanged), the new logic should be backwards compatible with v1.0.0 and v1.1.0 files. Note the new file format v1.2.0 will not be compatible with old logic.
• This can be achieved by created 2 sets of "json formatters", e.g. lockJSON_v1_1 (for old) and lockJSON_v1_2 (for new). All child formatters (definition, operators, distributed validators) would require the same.
• funcs func unmarshalLock_v1_1(*Lock, []byte) error should then implemented to contain the separate logic.
• Add backwards compatibility unit and smoke tests

Out of Scope

No other config upgrades included.

[corverroos]

@OisinKyne I think we should actually upgrade cluster-definition.operators.config_signature and
cluster-definition.operators.enr_signature to hex (not base58), as they are standard EIP712 signatures which are commonly hex with 0x prefix. Leave lock.signature_aggregate as base58 since that is a BLS sig.