lndservices: create new package for LND-related services

This package will contain services that interact with the LND service.
Currently, these services are spread across `lnd_services.go` and other
top-level files. As a starting point, this commit adds a new logging
subsystem. Subsequent commits will move existing services into this
new package.

Author: ffranr

lndservices/log.go

@@ -0,0 +1,26 @@
+package lndservices
+
+import (
+	"github.com/btcsuite/btclog/v2"
+)
+
+// Subsystem defines the logging code for this subsystem.
+const Subsystem = "LNDS"
+
+// log is a logger that is initialized with no output filters.  This
+// means the package will not perform any logging by default until the caller
+// requests it.
+var log = btclog.Disabled
+
+// DisableLog disables all library log output.  Logging output is disabled
+// by default until UseLogger is called.
+func DisableLog() {
+	UseLogger(btclog.Disabled)
+}
+
+// UseLogger uses a specified Logger to output package logging info.
+// This should be used in preference to SetLogWriter if the caller is also
+// using btclog.
+func UseLogger(logger btclog.Logger) {
+	log = logger
+}

log.go

@@ -5,6 +5,7 @@ import (
 	"github.com/lightninglabs/taproot-assets/address"
 	"github.com/lightninglabs/taproot-assets/authmailbox"
 	"github.com/lightninglabs/taproot-assets/commitment"
+	"github.com/lightninglabs/taproot-assets/lndservices"
 	"github.com/lightninglabs/taproot-assets/monitoring"
 	"github.com/lightninglabs/taproot-assets/proof"
 	"github.com/lightninglabs/taproot-assets/rfq"
@@ -127,6 +128,10 @@ func SetupLoggers(root *build.SubLoggerManager,
 	AddSubLogger(
 		root, authmailbox.Subsystem, interceptor, authmailbox.UseLogger,
 	)
+	AddSubLogger(
+		root, lndservices.Subsystem, interceptor,
+		lndservices.UseLogger,
+	)
 }
 
 // AddSubLogger is a helper method to conveniently create and register the