feat: add current price & track quantities

[filo87]

@hieronx current price is not available in portfolio runtime V1, we need to handle the different cases for V1 and V2.

  ActiveLoanInfoV2: {
    activeLoan: 'PalletLoansEntitiesLoansActiveLoan',
    presentValue: 'Balance',
    outstandingPrincipal: 'Balance',
    outstandingInterest: 'Balance',
    currentPrice: 'Option<Balance>',
  },
  ActiveLoanInfoV1: {
    activeLoan: 'PalletLoansEntitiesLoansActiveLoan',
    presentValue: 'Balance',
    outstandingPrincipal: 'Balance',
    outstandingInterest: 'Balance',
}

--> Planned for next sprint