Fix some issues in UpgradeToElectra

[jtraglia]

What type of PR is this?

Bug fix

What does this PR do? Why is it needed?

Primarily, this PR fixes some issues in UpgradeToElectra.

• The logic for calculating earliestExitEpoch wasn't quite right.
  • It was finding the max exit epoch, not the minimum.
  • I believe my changes should work as intended, though it still deviates from the spec.
• ExitBalanceToConsume and ConsolidationBalanceToConsume should be set to 0.
  • These were being set to the total active balance.
  • The copy-paste spec for this says they should be zero, so not sure.
    • Speaking of this, the godoc function is out of date, but this PR doesn't fix that.
    • I've chatted with Kasey some about a long-term fix for this type of issue.
• Fix tests & rename some variables.
  • I don't think names like lwvi are very readable.

Also, some unrelated fixes:

• Delete unused ProcessSyncAggregate alias.
• In PendingDeposit, Amount was specified in the wrong order.

Acknowledgements

• I have read CONTRIBUTING.md.
• I have made an appropriate entry to CHANGELOG.md.
• I have added a description to this PR with sufficient context for reviewers to understand this PR.

[terencechain]

A bunch of spec tests are failing after this change.

• TestMainnet_Electra_Transition
• TestMainnet_UpgradeToElectra

Are we sure it's the min? the spec looks max to me:

  exit_epochs = [v.exit_epoch for v in pre.validators if v.exit_epoch != FAR_FUTURE_EPOCH]
    if not exit_epochs:
        exit_epochs = [get_current_epoch(pre)]
    earliest_exit_epoch = max(exit_epochs) + 1

[jtraglia]

Are we sure it's the min? the spec looks max to me

Ah yes, you're right. I misread that. My fault. Will revert that change now.

[terencechain]

I dont think this is right either. We should assign them to churn limit based on total active balances

    post.exit_balance_to_consume = get_activation_exit_churn_limit(post)
    post.consolidation_balance_to_consume = get_consolidation_churn_limit(post)

[jtraglia]

Ugh. Once again you're right. I'm going to close this.