Figures out a way to migrate Staked SUI from a matured vault to the new vault

[pisuthd]

When redeeming, we unstake Staked SUI internally and attach SUI tokens to the vault object, allowing PT holders to redeem SUI tokens at a 1:1 ratio. We should find a way to migrate those Staked SUI objects to the new vault without losing rewards in-between.

[pisuthd]

We could implement a so-called 'Unstoppable Vault', where the new vault will keep growing and always include assets from the previous vault.

If you have a vault that has already matured, you would be able to claim the PT from the new vault and cover the PT from the starting epoch until the mature date