enable revive linter

cmd/q3rcon-proxy/main.go

@@ -1,3 +1,4 @@
+// Package main implements a command-line application for a Quake 3 RCON proxy server.
 package main
 
 import (
@@ -44,7 +45,7 @@ func main() {
 				Usage:    "Proxy and target ports (proxy:target)",
 				Sources:  cli.EnvVars("Q3RCON_PORTS_MAPPING"),
 				Required: true,
-				Action: func(ctx context.Context, cmd *cli.Command, v string) error {
+				Action: func(_ context.Context, _ *cli.Command, v string) error {
 					// Validate the ports mapping
 					for mapping := range strings.SplitSeq(v, ";") {
 						ports := strings.Split(mapping, ":")