Release 3.8.2.11: idle rev-cache, port-safe Connect, single-instance tray UX.

Faster unchanged polls; orphan-core cleanup on listen ports; clearer busy-port errors; cores only from binDir; incremental server list; CSP without Google Fonts; single-instance activates existing window; close-to-tray without kill-others or balloon.

Co-authored-by: Cursor <cursoragent@cursor.com>

cmd/vpnapp/gui_desktop.go

@@ -17,6 +17,7 @@ import (
 	"vpnclient/internal/core"
 	"vpnclient/internal/dockicon"
 	"vpnclient/internal/logbuf"
+	"vpnclient/internal/singleinstance"
 	"vpnclient/internal/trayhost"
 	"vpnclient/internal/update"
 )
@@ -27,6 +28,16 @@ func main() {
 	}
 	update.CleanupStaleDownloads()
 
+	releaseInstance, err := singleinstance.Lock("Navis")
+	if err != nil {
+		if err == singleinstance.ErrAlreadyRunning {
+			// Existing window was activated when possible.
+			return
+		}
+		fatalf("Не удалось получить single-instance lock:\n%v", err)
+	}
+	defer releaseInstance()
+
 	log.SetFlags(log.LstdFlags | log.Lshortfile)
 	log.Printf("Navis %s · GOMAXPROCS=%d NumCPU=%d", update.DisplayVersion(), runtime.GOMAXPROCS(0), runtime.NumCPU())
 
@@ -66,14 +77,18 @@ func main() {
 		fatalf("listen: %v", err)
 	}
 	a.APIToken = token
-	srv := &http.Server{Handler: a.Handler()}
+	srv := &http.Server{
+		Handler:           a.Handler(),
+		ReadHeaderTimeout: 5 * time.Second,
+		// No WriteTimeout: SSE /api/events is long-lived.
+	}
 	go func() {
 		_ = srv.Serve(ln)
 	}()
 
 	a.StartBackground()
 	dockicon.OnIconChange = trayhost.SetConnectedIcon
-	trayhost.Start("Navis", trayhost.Hooks{
+	trayOK := trayhost.Start("Navis", trayhost.Hooks{
 		Connect:    func() { _ = a.Connect() },
 		Disconnect: func() { _ = a.Disconnect() },
 		Show:       showMainWindow,
@@ -112,8 +127,9 @@ func main() {
 
 	w.SetTitle("Navis")
 	w.SetSize(500, 900, glaze.HintNone)
-	decorateWindow(w)
+	// Close→hide only when tray is alive; otherwise X would leave invisible zombies.
+	decorateWindow(w, trayOK)
 	w.Navigate(uiURL)
-	log.Printf("Navis UI: %s", uiURL)
+	log.Printf("Navis UI: %s (tray=%v hideOnClose=%v)", uiURL, trayOK, trayOK)
 	w.Run()
 }