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.

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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.
#include <interfaces/wallet.h>
#include <consensus/amount.h>
#include <interfaces/chain.h>
#include <interfaces/handler.h>
#include <policy/fees.h>
#include <primitives/transaction.h>
#include <rpc/server.h>
#include <script/standard.h>
#include <support/allocators/secure.h>
#include <sync.h>
#include <uint256.h>
#include <util/check.h>
#include <util/system.h>
#include <util/translation.h>
#include <util/ui_change_type.h>
#include <wallet/context.h>
#include <wallet/feebumper.h>
#include <wallet/fees.h>
#include <wallet/ismine.h>
#include <wallet/load.h>
#include <wallet/receive.h>
#include <wallet/rpc/wallet.h>
#include <wallet/spend.h>
#include <wallet/wallet.h>
#include <memory>