contractcourt: update GenSweepScript to return internal key

For the upcoming aux sweeper integration, the internal key is needed for
the call backs.

contractcourt/breach_arbitrator.go

@@ -149,7 +149,7 @@ type BreachConfig struct {
 	Estimator chainfee.Estimator
 
 	// GenSweepScript generates the receiving scripts for swept outputs.
-	GenSweepScript func() ([]byte, error)
+	GenSweepScript func() fn.Result[lnwallet.AddrWithKey]
 
 	// Notifier provides a publish/subscribe interface for event driven
 	// notifications regarding the confirmation of txids.
@@ -1517,7 +1517,7 @@ func (b *BreachArbitrator) sweepSpendableOutputsTxn(txWeight lntypes.WeightUnit,
 	// sweep the funds to.
 	// TODO(roasbeef): possibly create many outputs to minimize change in
 	// the future?
-	pkScript, err := b.cfg.GenSweepScript()
+	pkScript, err := b.cfg.GenSweepScript().Unpack()
 	if err != nil {
 		return nil, err
 	}
@@ -1545,7 +1545,7 @@ func (b *BreachArbitrator) sweepSpendableOutputsTxn(txWeight lntypes.WeightUnit,
 
 	// We begin by adding the output to which our funds will be deposited.
 	txn.AddTxOut(&wire.TxOut{
-		PkScript: pkScript,
+		PkScript: pkScript.DeliveryAddress,
 		Value:    sweepAmt,
 	})
 

contractcourt/breach_arbitrator_test.go

@@ -2138,11 +2138,15 @@ func createTestArbiter(t *testing.T, contractBreaches chan *ContractBreachEvent,
 		CloseLink: func(_ *wire.OutPoint, _ ChannelCloseType) {},
 		DB:        db.ChannelStateDB(),
 		Estimator: chainfee.NewStaticEstimator(12500, 0),
-		GenSweepScript:     func() ([]byte, error) { return nil, nil },
+		GenSweepScript: func() fn.Result[lnwallet.AddrWithKey] {
+			return fn.Ok(lnwallet.AddrWithKey{})
+		},
 		ContractBreaches: contractBreaches,
 		Signer:           signer,
 		Notifier:         notifier,
-		PublishTransaction: func(_ *wire.MsgTx, _ string) error { return nil },
+		PublishTransaction: func(_ *wire.MsgTx, _ string) error {
+			return nil
+		},
 		Store: store,
 	})
 

server.go

@@ -1177,16 +1177,9 @@ func newServer(cfg *Config, listenAddrs []net.Addr,
 			CloseLink: closeLink,
 			DB:        s.chanStateDB,
 			Estimator: s.cc.FeeEstimator,
-			GenSweepScript: func() ([]byte, error) {
-				addr, err := newSweepPkScriptGen(
-					cc.Wallet, netParams,
-				)().Unpack()
-				if err != nil {
-					return nil, err
-				}
-
-				return addr.DeliveryAddress, nil
-			},
+			GenSweepScript: newSweepPkScriptGen(
+				cc.Wallet, s.cfg.ActiveNetParams.Params,
+			),
 			Notifier:           cc.ChainNotifier,
 			PublishTransaction: cc.Wallet.PublishTransaction,
 			ContractBreaches:   contractBreaches,