fix(cli): avoid warning when HTTP log server is not yet available

Treat "socket missing" (ENOENT) and connection refused as expected when
probing the log server, and only log when the error indicates something
unexpected. This prevents noisy warnings when the log server has not
started yet.

Discover while doing captive portal tests.

cmd/cli/cli.go

@@ -238,7 +238,7 @@ func run(appCallback *AppCallback, stopCh chan struct{}) {
 
 	// Test if HTTP log server is available
 	if err := hlc.Ping(); err != nil {
-		if !errConnectionRefused(err) {
+		if !errLogServerUnavailable(err) {
 			p.Warn().Err(err).Msg("Unable to ping log server")
 		}
 	} else {