peer+feature: start to signal the prod rbf coop close bit

In this commit, we start to signal the prod bit for the rbf coop close
feature. We keep our signaling of the staging bit in place to ensure
the protocol continues to work between those nodes in the wild that are
still signaling the bit.

Fixes https://github.com/lightningnetwork/lnd/issues/9852

feature/default_sets.go

@@ -107,4 +107,8 @@ var defaultSetDesc = setDesc{
 		SetInit:    {}, // I
 		SetNodeAnn: {}, // N
 	},
+	lnwire.RbfCoopCloseOptional: {
+		SetInit:    {}, // I
+		SetNodeAnn: {}, // N
+	},
 }

feature/manager.go

@@ -219,6 +219,7 @@ func newManager(cfg Config, desc setDesc) (*Manager, error) {
 		}
 		if cfg.NoRbfCoopClose {
 			raw.Unset(lnwire.RbfCoopCloseOptionalStaging)
+			raw.Unset(lnwire.RbfCoopCloseOptional)
 		}
 
 		for _, custom := range cfg.CustomFeatures[set] {