Refactor validator oracle reports to support proofs

[shanejearley]

EigenLayer requires that pod owners submit proofs (generated using Telepathy's Succinct circuits) to restake and withdraw. Their integration for generating these proofs is near completion, and we can refactor the oracle flow to handle this case when it is ready. We could also use similar proofs to verify validator statuses and combined balance sums (the latter will be applicable to total Beacon or swept balances).

EIP 4788 (beacon block root in the EVM) will make this approach become somewhat trustless.