Include reserved part of 0.0.800 balance in end-of-period NodeStakeUpdateTransaction

[tinker-michaelj]

Problem

The synthetic NodeStakeUpdateTransactionBody does not include several values that mirror node operators would need to conveniently the amount of the 0.0.800 balance that is "reserved " to pay staking rewards earned but not collected.

Solution

Add protobuf fields

message NodeStakeUpdateTransactionBody {
  ...

  /**
   * The amount of the staking reward funds (account 0.0.800) reserved to pay pending rewards that 
   * have been earned but not collected.
   */
  int64 reserved_staking_rewards = 10;

  /**
   * The unreserved balance of account 0.0.800 at the close of the just-ending period; this value is 
   * used to compute the HIP-782 balance ratio.
   */
  int64 unreserved_staking_reward_balance = 11;

  /**
   * The unreserved tinybar balance of account 0.0.800 required to achieve the maximum per-hbar reward 
   * rate; please see HIP-782 for details.
   */
  int64 reward_balance_threshold = 12;

  /**
   * The maximum amount of tinybar that can be staked for reward while still achieving the maximum 
   * per-hbar reward rate; please see HIP-782 for details.
   */
  int64 max_stake_rewarded = 13;
}

and populate them in the obvious way.

Alternatives

No response

[tinker-michaelj]

Done.