ax(node): rename idx to separatorIndex in parseComment

AX Principle 1 — predictable names over short names. idx is an
abbreviation requiring a mental mapping; separatorIndex names the
variable by its role (the index of the = separator character).

Co-Authored-By: Charon <charon@lethean.io>

pkg/node/lethean.go

@@ -144,9 +144,9 @@ func DiscoverGateways(daemonURL string) []PoolGateway {
 func parseComment(comment string) map[string]string {
 	result := make(map[string]string)
 	for _, part := range strings.Split(comment, ";") {
-		idx := strings.IndexByte(part, '=')
-		if idx > 0 {
-			result[part[:idx]] = part[idx+1:]
+		separatorIndex := strings.IndexByte(part, '=')
+		if separatorIndex > 0 {
+			result[part[:separatorIndex]] = part[separatorIndex+1:]
 		}
 	}
 	return result