feat: basic pectra compatibility

[wadealexc]

Motivation:

Add basic pectra compatibility to EigenPods, supporting EIP-7002 and EIP-7251

Modifications:

Add 2 methods to EigenPod.sol. See full method docs in IEigenPod.sol - they're long, so I didn't copy them here 😄

/**
 * @param srcPubkey the pubkey of the source validator for the consolidation
 * @param targetPubkey the pubkey of the target validator for the consolidation
 * @dev Note that if srcPubkey == targetPubkey, this is a "switch request," and will
 * change the validator's withdrawal credential type from 0x01 to 0x02.
 * For more notes on usage, see `requestConsolidation`
 */
struct ConsolidationRequest {
  bytes srcPubkey;
  bytes targetPubkey;
}

/**
 * @param pubkey the pubkey of the validator to withdraw from
 * @param amountGwei the amount (in gwei) to withdraw from the beacon chain to the pod
 * @dev Note that if amountGwei == 0, this is a "full exit request," and will fully exit
 * the validator to the pod.
 * For more notes on usage, see `requestWithdrawal`
 */
struct WithdrawalRequest {
  bytes pubkey;
  uint64 amountGwei;
}

/// SEE FULL DOCS IN IEigenPod.sol
function requestConsolidation(
  ConsolidationRequest[] calldata requests
) external payable onlyOwnerOrProofSubmitter;

/// SEE FULL DOCS IN IEigenPod.sol
function requestWithdrawal(
  WithdrawalRequest[] calldata requests
) external payable onlyOwnerOrProofSubmitter;

Add 4 events to EigenPod.sol:

/// @notice Emitted when a consolidation request is initiated where source == target
event SwitchToCompoundingRequested(bytes32 indexed validatorPubkeyHash);

/// @notice Emitted when a standard consolidation request is initiated
event ConsolidationRequested(bytes32 indexed sourcePubkeyHash, bytes32 indexed targetPubkeyHash);

/// @notice Emitted when a withdrawal request is initiated where request.amountGwei == 0
event ExitRequested(bytes32 indexed validatorPubkeyHash);

/// @notice Emitted when a partial withdrawal request is initiated
event WithdrawalRequested(bytes32 indexed validatorPubkeyHash, uint64 withdrawalAmountGwei);

Result:

EigenPods will support Pectra features, allowing the pod owner or proof submitter of a pod to initiate consolidations and withdrawals via the EIP-7002 and EIP-7521 predeploys.

[bowenli86]

events looks good to me ✅