lnwallet: increase legacy fee limit threshold to 1k sats

In this commit, we increase the legacy fee limit threshold (the amount
below which we'll allow 100% of funds to go to fees for the non-v2 RPC
calls) from 50 sats to 1k sats.

lnwallet/parameters.go

@@ -8,10 +8,13 @@ import (
 	"github.com/lightningnetwork/lnd/lnwire"
 )
 
-const (
+var (
 	// RoutingFee100PercentUpTo is the cut-off amount we allow 100% fees to
 	// be charged up to.
-	RoutingFee100PercentUpTo lnwire.MilliSatoshi = 50_000
+	RoutingFee100PercentUpTo = lnwire.NewMSatFromSatoshis(1_000)
+)
+
+const (
 
 	// DefaultRoutingFeePercentage is the default off-chain routing fee we
 	// allow to be charged for a payment over the RoutingFee100PercentUpTo

lnwallet/parameters_test.go

@@ -24,12 +24,12 @@ func TestDefaultRoutingFeeLimitForAmount(t *testing.T) {
 			expectedLimit: 1,
 		},
 		{
-			amount:        50_000,
-			expectedLimit: 50_000,
+			amount:        lnwire.NewMSatFromSatoshis(1_000),
+			expectedLimit: lnwire.NewMSatFromSatoshis(1_000),
 		},
 		{
-			amount:        50_001,
-			expectedLimit: 2_500,
+			amount:        lnwire.NewMSatFromSatoshis(1_001),
+			expectedLimit: 50_050,
 		},
 		{
 			amount:        5_000_000_000,
@@ -42,7 +42,7 @@ func TestDefaultRoutingFeeLimitForAmount(t *testing.T) {
 
 		t.Run(fmt.Sprintf("%d sats", test.amount), func(t *testing.T) {
 			feeLimit := DefaultRoutingFeeLimitForAmount(test.amount)
-			require.Equal(t, test.expectedLimit, feeLimit)
+			require.Equal(t, int64(test.expectedLimit), int64(feeLimit))
 		})
 	}
 }