Dynamic min-relay-fee and dust amount (#280)

* [btc-embedded] add chainfee.Estimator and extraAPI interfaces

* dynamic fee amount

* dynamic dust amount

* [client] fix linter errors

* [domain] fix unit tests

* [server] return dust amount in GetInfo RPC

* [sdk] fix lnd dependencie

* go work sync

* fix witness stack size forfeit tx size estimator

* remove hardcoded fee values in covenant txbuilder

* lower liquid feerate

* fix after reviews

* go work sync

common/fees.go

@@ -0,0 +1,21 @@
+package common
+
+import (
+	"github.com/btcsuite/btcd/txscript"
+	"github.com/lightningnetwork/lnd/input"
+)
+
+var TreeTxSize = (&input.TxWeightEstimator{}).
+	AddTaprootKeySpendInput(txscript.SigHashDefault). // parent
+	AddP2TROutput().                                  // left child
+	AddP2TROutput().                                  // right child
+	VSize()
+
+// liquid node size is 2x the bitcoin node size (avoid min-relay-fee issues with the low fee rate on liquid)
+var CovenantTreeTxSize = TreeTxSize * 2
+
+var ConnectorTxSize = (&input.TxWeightEstimator{}).
+	AddP2WKHInput().
+	AddP2WKHOutput().
+	AddP2WKHOutput().
+	VSize()