Fix staking with unconfirmed transactions

FundsPreservationRule compares total inputs and outputs in block. If
block contains unconfirmed transactions, their input can't be found in
UTXOs. In that case, inputs are searched in transactions of validating
block.

Sources/DeStream.DeStreamD/Program.cs

@@ -35,7 +35,7 @@ namespace DeStream.DeStreamD
                     .UseDeStreamPosConsensus()
                     .UseDeStreamMempool()
                     .UseDeStreamWallet()
-                    .AddPowPosMining()
+                    .AddDeStreamPowPosMining()
                     .UseApi()
                     .UseApps()
                     .AddRPC()

Sources/Stratis.Bitcoin.Features.Consensus/Rules/CommonRules/DeStreamFundsPreservationRule.cs

@@ -18,9 +18,11 @@ namespace Stratis.Bitcoin.Features.Consensus.Rules.CommonRules
                 (context as UtxoRuleContext ??
                  throw new NotSupportedException($"Rule context must be {nameof(UtxoRuleContext)}")).UnspentOutputSet;
             long totalIn = context.ValidationContext.BlockToValidate.Transactions.SelectMany(p =>
-                    p.Inputs.RemoveChangePointer().Where(q => q.PrevOut != null)
-                        .Select(q => inputs.AccessCoins(q.PrevOut.Hash)?.TryGetOutput(q.PrevOut.N)?.Value ?? 0))
-                .Sum(p => p ?? 0);
+                p.Inputs.RemoveChangePointer().Where(q => q.PrevOut != null).Select(q =>
+                    inputs.AccessCoins(q.PrevOut.Hash)?.TryGetOutput(q.PrevOut.N)?.Value ??
+                    context.ValidationContext.BlockToValidate.Transactions
+                        .SingleOrDefault(r => r.GetHash() == q.PrevOut.Hash)?.Outputs[q.PrevOut.N]?.Value ??
+                    throw new ConsensusErrorException(ConsensusErrors.BadTransactionMissingInput))).Sum(p => p ?? 0);
 
             long totalOut = context.ValidationContext.BlockToValidate.Transactions.SelectMany(p => p.Outputs.Select(q => q.Value))
                 .Sum(p => p);