Fixed the format

pkg/pid/pidfile.go

@@ -6,11 +6,13 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
+	"net"
 	"net/http"
 	"os"
 	"path/filepath"
 	"sync"
 	"time"
+	"strconv"
 
 	"github.com/sipeed/picoclaw/pkg/config"
 	"github.com/sipeed/picoclaw/pkg/logger"
@@ -50,7 +52,7 @@ func generateToken() string {
 // then verifies the reported PID matches expectedPID to confirm the process
 // is actually a picoclaw gateway and not a foreign service on the same port.
 func isGatewayAlive(host string, port int, expectedPID int) bool {
-	url := fmt.Sprintf("http://%s:%d/health", host, port)
+	url := "http://" + net.JoinHostPort(host, strconv.Itoa(port)) + "/health"
 	client := &http.Client{Timeout: 2 * time.Second}
 	resp, err := client.Get(url)
 	if err != nil {

pkg/pid/pidfile_test.go

@@ -124,7 +124,6 @@ func TestWritePidFileNonLocalhostHost(t *testing.T) {
 	}
 }
 
-
 // verifies that a foreign process reusing a crashed gateway's PID is treated as stale.
 func TestWritePidFileForeignPIDReuse(t *testing.T) {
 	dir := tmpDir(t)