feat: Migrate fractional balance state from evmutil to precisebank

[drklee3]

Description

• Set fractional balance in x/precisebank from all balances in x/evmutil
• Delete corresponding state in x/evmutil

Notes

This is treated as a migration for x/evmutil, not x/precisebank, as it is the store of evmutil that will be removed (breaking change)

• Next PR will be to remove the accounts from x/evmutil, genesis, keeper methods, types etc.
• This PR includes a copy of the necessary types/keys to function after the accounts are removed.
• Moving reserve balances to precisebank module is not a store migration, so it will be added to the upgrade handler.