fix(xray): retry a failed pending-restart instead of dropping the config change

The 30s cron consumed the need-restart flag with IsNeedRestartAndSetFalse before
calling RestartXray and only logged a failure. If RestartXray failed early (a
transient GetXrayConfig DB error) the old process kept running the old config,
the crash detector saw a running process and never retried, and the flag stayed
cleared — so an admin's saved change silently never reached the core. Move the
consume/restart/retry into ApplyPendingRestart, which re-arms the flag on
failure so the next tick retries.

internal/web/service/xray.go

@@ -1188,6 +1188,20 @@ func (s *XrayService) IsNeedRestartAndSetFalse() bool {
 	return isNeedXrayRestart.CompareAndSwap(true, false)
 }
 
+// ApplyPendingRestart consumes the need-restart flag and restarts Xray. If the
+// restart fails (for example GetXrayConfig hits a transient DB error and leaves
+// the old process running), it re-arms the flag so the next tick retries instead
+// of silently dropping the pending config change.
+func (s *XrayService) ApplyPendingRestart() {
+	if !s.IsNeedRestartAndSetFalse() {
+		return
+	}
+	if err := s.RestartXray(false); err != nil {
+		logger.Error("restart xray failed:", err)
+		s.SetToNeedRestart()
+	}
+}
+
 // DidXrayCrash checks if Xray crashed by verifying it's not running and wasn't manually stopped.
 func (s *XrayService) DidXrayCrash() bool {
 	return !s.IsXrayRunning() && !isManuallyStopped.Load()

internal/web/service/xray_restart_test.go

@@ -21,3 +21,26 @@ func TestRestartXrayRespectsManualStop(t *testing.T) {
 		t.Fatal("a non-forced restart cleared a deliberate manual stop and would revive xray")
 	}
 }
+
+// When the pending-restart reconcile consumes the need-restart flag but the
+// restart itself fails, the flag must be re-armed so the config change is
+// retried rather than silently dropped.
+func TestApplyPendingRestartReArmsFlagOnFailure(t *testing.T) {
+	setupSettingTestDB(t)
+	if err := (&SettingService{}).saveSetting("xrayTemplateConfig", "{ not valid json"); err != nil {
+		t.Fatalf("seed template: %v", err)
+	}
+	t.Cleanup(func() {
+		isManuallyStopped.Store(false)
+		isNeedXrayRestart.Store(false)
+	})
+	isManuallyStopped.Store(false)
+
+	svc := &XrayService{}
+	svc.SetToNeedRestart()
+	svc.ApplyPendingRestart()
+
+	if !isNeedXrayRestart.Load() {
+		t.Fatal("a failed restart must re-arm the need-restart flag so the pending config change is retried")
+	}
+}

internal/web/web.go

@@ -314,12 +314,7 @@ func (s *Server) startTask(restartXray bool) {
 
 	// Check if xray needs to be restarted every 30 seconds
 	_, _ = s.cron.AddFunc(cadenceXrayRestart, func() {
-		if s.xrayService.IsNeedRestartAndSetFalse() {
-			err := s.xrayService.RestartXray(false)
-			if err != nil {
-				logger.Error("restart xray failed:", err)
-			}
-		}
+		s.xrayService.ApplyPendingRestart()
 	})
 
 	go func() {