tapdb: return lease owner and expiry for managed UTXOs

This should help us track down issues when assets aren't unlocked even
though they should be.

We also extend an existing unit test to ensure these values are properly
set.

Author: Roasbeef

tapdb/assets_store.go

@@ -417,6 +417,14 @@ type ManagedUTXO struct {
 	// TapscriptSibling is the serialized tapscript sibling preimage of
 	// this asset. This will usually be blank.
 	TapscriptSibling []byte
+
+	// LeaseOwner is the identifier of the lease owner of this UTXO. If
+	// blank, this UTXO isn't leased.
+	LeaseOwner []byte
+
+	// LeaseExpiry is the expiry time of the lease on this UTXO. If the
+	// zero, then this UTXO isn't leased.
+	LeaseExpiry time.Time
 }
 
 // AssetHumanReadable is a subset of the base asset struct that only includes
@@ -1125,7 +1133,7 @@ func (a *AssetStore) FetchManagedUTXOs(ctx context.Context) (
 			return nil, err
 		}
 
-		managedUtxos[i] = &ManagedUTXO{
+		utxo := &ManagedUTXO{
 			OutPoint:    anchorPoint,
 			OutputValue: btcutil.Amount(u.AmtSats),
 			InternalKey: keychain.KeyDescriptor{
@@ -1140,7 +1148,13 @@ func (a *AssetStore) FetchManagedUTXOs(ctx context.Context) (
 			TaprootAssetRoot: u.TaprootAssetRoot,
 			MerkleRoot:       u.MerkleRoot,
 			TapscriptSibling: u.TapscriptSibling,
+			LeaseOwner:       u.LeaseOwner,
 		}
+		if u.LeaseExpiry.Valid {
+			utxo.LeaseExpiry = u.LeaseExpiry.Time
+		}
+
+		managedUtxos[i] = utxo
 	}
 
 	return managedUtxos, nil

tapdb/assets_store_test.go

@@ -1465,8 +1465,11 @@ func TestAssetExportLog(t *testing.T) {
 	require.NoError(t, err)
 	require.Len(t, utxos, 3)
 
-	// First UTXO should remain unchanged.
+	// First UTXO should remain unchanged. It should now have a lease
+	// expiry and owner set.
 	require.Equal(t, assetGen.anchorPoints[0], utxos[0].OutPoint)
+	require.Equal(t, leaseOwner[:], utxos[0].LeaseOwner[:])
+	require.NotZero(t, utxos[0].LeaseExpiry)
 
 	// Second UTXO will be our new one.
 	newUtxo := utxos[1]