Epoch system

Because staking rewards are unpredictable and could fluctuate due to validator profitability, to ensure fairness, an epoch system is employed to ensure the time that a wstTAO is minted or redeemed is in sync with a reserve number update.

All mint and redemption requests are put into queue until a certain time (currently every two hours) and are processed in batch.

For every epoch, all redeems will be processed based on the NAV (net asset value) of the last epoch. Then the reserve will be updated and the NAV will be cached. All mints will be based on the new cached nav and reserve cache will be updated with the mint.

The best case is that all mints and redeems will be real time. However, the max number of oracle updates will be once per epoch.

The oracle will pause updating the NAV if there was no mint requests during the past epoch. Max pause will be 24 hours.