A user reported to me that they are unable to create a PSBT with a legacy watchonly wallet when they use the GUI. They get an error "The amount exceeds your balance".

I think the issue is that the GUI will retrieve the wallet's balance via `AvailableCoins` before calling `CreateTransaction`. This call to `AvailableCoins` is resulting in fewer coins being returned with recent changes to how `AvailableCoins` works, particularly with additional filtering of spendable coins and preset coins.

***

Note that this does not effect descriptor wallets. A workaround for this issue is to switch to using descriptor wallets. An existing legacy wallet can be turned into a descriptor wallet using the `migratewallet` RPC. However many watchonly legacy wallets are likely the result of importing descriptors via `importmulti`. For such wallets, I recommend creating a new descriptor wallet and re-importing the descriptors.
std::string strAddress = rcp.address.toStdString();
            CTxDestination dest = DecodeDestination(strAddress);
            std::string strLabel = rcp.label.toStdString();
            {
                
                std::string name;
                if (!m_wallet->getAddress(
                     dest, &name,  nullptr,  nullptr))
                {
                    m_wallet->setAddressBook(dest, strLabel, "send");
                }
                else if (name != strLabel)
                {
                    m_wallet->setAddressBook(dest, strLabel, ""); 
                }
            }
        }
        Q_EMIT coinsSent(this, rcp, transaction_array);
    }
    checkBalanceChanged(m_wallet->getBalances()); 
}
OptionsModel* WalletModel::getOptionsModel() const
{
    return optionsModel;
}
AddressTableModel* WalletModel::getAddressTableModel() const
{
    return addressTableModel;
}
TransactionTableModel* WalletModel::getTransactionTableModel() const