Validator CLI

[wemeetagain]

Is your feature request related to a problem? Please describe.
We need a validator CLI to run validators from the command line.

Describe the solution you'd like
A validator CLI with:

• ability to run N validators at once
• the big task here will be handling on-disk persistence, managing keys, user secrets, etc and passing them successfully to the validator nodes
• safely handle user secrets
• we likely only need to handle 'keystores', rather than 'walletstores'
• consistent code style, building off the current beacon command. Eg: Create a validator command, in the same way
• implementation following community standards and community discussion
  • ideally following closely with other client decisions, picking the best ideas and using them

Describe alternatives you've considered
No CLI? 😭

Additional context
Related to the validator CLI we may need a wallet CLI command. Depending on judgement, that may be completed in parallel or as a prerequisite.

EIP-2335
ethereum/eth2.0-pm#161
See other clients validator clients:
https://github.com/sigp/lighthouse/tree/master/validator_client
https://github.com/PegaSysEng/teku
https://github.com/prysmaticlabs/prysm/
https://github.com/status-im/nimbus
https://github.com/ethereum/trinity/tree/master/eth2

See Eth2 R&D #key-management discord for important discussion on validator key management

[dapplion]

Do you imagine it being close to ethdo https://github.com/wealdtech/ethdo/blob/master/docs/usage.md ?

[wemeetagain]

I think that would be more related to an account/wallet command, which would manage the on-disk keystores, in a lodestar-opinionated way.

The validator cli command would read on-disk keystores, as configured via cli and on-disk configuration, and use those to init Validators from lodestar-validator.

[wemeetagain]

resolved with #1093