multi: add SpewLogClosure to avoid code repetition

lnutils/log.go

@@ -1,5 +1,7 @@
 package lnutils
 
+import "github.com/davecgh/go-spew/spew"
+
 // LogClosure is used to provide a closure over expensive logging operations so
 // don't have to be performed when the logging level doesn't warrant it.
 type LogClosure func() string
@@ -15,3 +17,11 @@ func (c LogClosure) String() string {
 func NewLogClosure(c func() string) LogClosure {
 	return LogClosure(c)
 }
+
+// SpewLogClosure takes an interface and returns the string of it created from
+// `spew.Sdump` in a LogClosure.
+func SpewLogClosure(a any) LogClosure {
+	return func() string {
+		return spew.Sdump(a)
+	}
+}