routing+lnrpc+lncli: allow setting min htlc policy

cmd/lncli/commands.go

@@ -3459,6 +3459,12 @@ var updateChannelPolicyCommand = cli.Command{
 			Usage: "the CLTV delta that will be applied to all " +
 				"forwarded HTLCs",
 		},
+		cli.Uint64Flag{
+			Name: "min_htlc_msat",
+			Usage: "if set, the min HTLC size that will be applied " +
+				"to all forwarded HTLCs. If unset, the min HTLC " +
+				"is left unchanged.",
+		},
 		cli.Uint64Flag{
 			Name: "max_htlc_msat",
 			Usage: "if set, the max HTLC size that will be applied " +
@@ -3581,6 +3587,11 @@ func updateChannelPolicy(ctx *cli.Context) error {
 		MaxHtlcMsat:   ctx.Uint64("max_htlc_msat"),
 	}
 
+	if ctx.IsSet("min_htlc_msat") {
+		req.MinHtlcMsat = ctx.Uint64("min_htlc_msat")
+		req.MinHtlcMsatSpecified = true
+	}
+
 	if chanPoint != nil {
 		req.Scope = &lnrpc.PolicyUpdateRequest_ChanPoint{
 			ChanPoint: chanPoint,