Release 3.8.1.1: lighter idle UI poll, core cache, multicore ping.

Reduce idle CPU (cheap PollUI, binary cache, logbuf cap, DOM fingerprint),
speed ping/AWG HostPort, CopyBuffer pool; ship arm64 build and update notes.

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

internal/core/manager.go

@@ -14,6 +14,7 @@ import (
 	"time"
 
 	"vpnclient/internal/config"
+	"vpnclient/internal/corebin"
 	"vpnclient/internal/linknorm"
 	"vpnclient/internal/protocols/awg"
 	"vpnclient/internal/protocols/hysteria2"
@@ -277,6 +278,76 @@ func (m *Manager) Config() *config.Config {
 	return m.cfg.Clone()
 }
 
+// UIPoll is a cheap manager snapshot for GUI polling (no JSON deep-clone of all proxies).
+type UIPoll struct {
+	Status         Status
+	Active         string
+	SystemProxy    bool
+	Subscription   string
+	ActiveProxy    string
+	ActiveProtocol config.Protocol
+	Profiles       []config.ProfileInfo
+	Hy2            Hy2Options
+	BinDir         string
+}
+
+// PollUI gathers status + profile list under one lock without Config().Clone().
+func (m *Manager) PollUI(includeSecrets bool) UIPoll {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+
+	out := UIPoll{
+		Status:       Status{SystemProxy: m.sys.Enabled()},
+		BinDir:       m.binDir,
+		SystemProxy:  false,
+		Subscription: "",
+		Hy2:          Hy2Options{Congestion: "bbr", BBRProfile: "standard"},
+	}
+	if m.cfg != nil {
+		out.Active = m.cfg.Active
+		out.SystemProxy = m.cfg.SystemProxy
+		out.Subscription = m.cfg.SubscriptionURL
+		if includeSecrets {
+			out.Profiles = m.cfg.ListProfiles()
+		} else {
+			out.Profiles = m.cfg.ListProfilesForPoll()
+		}
+		if p, err := m.cfg.ActiveProfile(); err == nil {
+			out.Active = p.Name
+			out.ActiveProxy = p.Proxy
+			out.ActiveProtocol = p.Protocol
+			out.Hy2 = Hy2Options{
+				Congestion:    p.Hy2Congestion,
+				BBRProfile:    p.Hy2BBRProfile,
+				BandwidthUp:   p.Hy2BandwidthUp,
+				BandwidthDown: p.Hy2BandwidthDown,
+				Obfs:          p.Hy2Obfs,
+				ObfsPassword:  p.Hy2ObfsPassword,
+				SNI:           p.Hy2SNI,
+				Insecure:      p.Hy2Insecure,
+				PinSHA256:     p.Hy2PinSHA256,
+				FastOpen:      p.Hy2FastOpen,
+				Lazy:          p.Hy2Lazy,
+				HopInterval:   p.Hy2HopInterval,
+			}
+		}
+	}
+	if m.engine != nil && m.engine.Running() {
+		out.Status.Connected = true
+		if m.profile != nil {
+			out.Status.Profile = m.profile.Name
+			out.Status.Protocol = m.profile.Protocol
+		}
+		if hp, ok := m.engine.LocalHTTPProxy(); ok {
+			out.Status.HTTPProxy = hp
+		}
+		if sp, ok := m.engine.LocalSOCKSProxy(); ok {
+			out.Status.SOCKSProxy = sp
+		}
+	}
+	return out
+}
+
 func (m *Manager) SetSystemProxy(enabled bool) {
 	m.mu.Lock()
 	defer m.mu.Unlock()
@@ -572,24 +643,37 @@ func (m *Manager) EnsureCore(proto config.Protocol) (string, error) {
 	}
 	m.mu.Unlock()
 
+	var (
+		path string
+		err  error
+	)
 	switch proto {
 	case config.ProtocolHysteria2:
-		return hysteria2.EnsureBinary(binDir)
+		path, err = hysteria2.EnsureBinary(binDir)
 	case config.ProtocolAWG:
-		return awg.EnsureBinary(binDir)
+		path, err = awg.EnsureBinary(binDir)
 	case config.ProtocolVLESS, config.ProtocolVMess, config.ProtocolTrojan:
-		return xray.EnsureBinary(binDir)
+		path, err = xray.EnsureBinary(binDir)
 	default:
-		return naive.EnsureBinary(binDir)
+		path, err = naive.EnsureBinary(binDir)
+		proto = config.ProtocolNaive
 	}
+	if err != nil {
+		return "", err
+	}
+	corebin.Set(corebin.CacheKey(binDir, corebin.ProtoKey(string(proto))), path)
+	return path, nil
 }
 
 // EnsureAllCores installs naive + hysteria2 + xray cores (AWG is embedded).
+// Downloads run in parallel (one goroutine per core) to use multiple CPU cores / network.
 func (m *Manager) EnsureAllCores() (map[string]string, error) {
 	m.mu.Lock()
 	binDir := m.binDir
 	m.mu.Unlock()
 
+	corebin.Invalidate()
+
 	type item struct {
 		key  string
 		path string
@@ -623,6 +707,7 @@ func (m *Manager) EnsureAllCores() (map[string]string, error) {
 			continue
 		}
 		out[it.key] = it.path
+		corebin.Set(corebin.CacheKey(binDir, it.key), it.path)
 	}
 	return out, first
 }