watchtower: uses P2TR for sweep, delivery, and reward addresses

In this commit, we modify the watch tower to use P2TR addrs for just
about anything sweep related.

One eye sore in this diff are the changes to
`backup_task_internal_test.go`. All the values are hard coded, and now
either differ by a value of 48, or needed to be modified to account for
the new assumptions propagated to rewards values and fees.

watchtower/lookout/justice_descriptor.go

@@ -10,6 +10,7 @@ import (
 	"github.com/btcsuite/btcd/btcutil/txsort"
 	"github.com/btcsuite/btcd/txscript"
 	"github.com/btcsuite/btcd/wire"
+	"github.com/davecgh/go-spew/spew"
 	"github.com/lightningnetwork/lnd/input"
 	"github.com/lightningnetwork/lnd/watchtower/blob"
 	"github.com/lightningnetwork/lnd/watchtower/wtdb"
@@ -228,8 +229,8 @@ func (p *JusticeDescriptor) assembleJusticeTxn(txWeight int64,
 		i := inputIndex[inp.outPoint]
 		justiceTxn.TxIn[i].Witness = inp.witness
 
-		// Validate the reconstructed witnesses to ensure they are valid
-		// for the breached inputs.
+		// Validate the reconstructed witnesses to ensure they are
+		// valid for the breached inputs.
 		vm, err := txscript.NewEngine(
 			inp.txOut.PkScript, justiceTxn, i,
 			txscript.StandardVerifyFlags,
@@ -239,7 +240,9 @@ func (p *JusticeDescriptor) assembleJusticeTxn(txWeight int64,
 			return nil, err
 		}
 		if err := vm.Execute(); err != nil {
-			return nil, err
+			log.Debugf("Failed to validate justice transaction: %s",
+				spew.Sdump(justiceTxn))
+			return nil, fmt.Errorf("error validating TX: %v", err)
 		}
 	}
 
@@ -300,6 +303,9 @@ func (p *JusticeDescriptor) CreateJusticeTxn() (*wire.MsgTx, error) {
 
 	sweepInputs = append(sweepInputs, toLocalInput)
 
+	log.Debugf("Found to local witness output=%#v, stack=%v",
+		toLocalInput.txOut, toLocalInput.witness)
+
 	// If the justice kit specifies that we have to sweep the to-remote
 	// output, we'll also try to assemble the output and add it to weight
 	// estimate if successful.
@@ -310,6 +316,9 @@ func (p *JusticeDescriptor) CreateJusticeTxn() (*wire.MsgTx, error) {
 		}
 		sweepInputs = append(sweepInputs, toRemoteInput)
 
+		log.Debugf("Found to remote witness output=%#v, stack=%v",
+			toRemoteInput.txOut, toRemoteInput.witness)
+
 		if p.JusticeKit.BlobType.IsAnchorChannel() {
 			weightEstimate.AddWitnessInput(input.ToRemoteConfirmedWitnessSize)
 		} else {