feat: 支持 Windows x86_64 平台编译

- 新增 WinTun TUN 设备实现(tun_windows.go),无需安装驱动,
  wintun.dll 嵌入 exe 运行时自动释放
- 新增 Windows 路由管理(route_windows.go),使用 route/netsh 命令
- 新增 Windows 路径(paths_windows.go),使用 %APPDATA%/%LOCALAPPDATA%
- 拆分 daemon 启动逻辑:launch_unix.go(Setsid) / launch_windows.go
  (CREATE_NEW_PROCESS_GROUP),公共代码提取到 launch_common.go
- 拆分提权逻辑:elevation_darwin.go(osascript) / elevation_windows.go
  (ShellExecute UAC) / elevation_other.go(pkexec)
- IPCSocketPath 按平台分散,Windows 用 %TEMP%\lmvpn.sock
- daemon 二进制名用编译时常量(daemonBinaryName),按平台选定 .exe 后缀
- Makefile 新增 build-windows 目标
- 重新标记 !darwin 文件为 !darwin && !windows

internal/ui/daemon.go

@@ -3,7 +3,6 @@ package ui
 import (
 	"fmt"
 	"os"
-	"os/exec"
 	"path/filepath"
 	"time"
 
@@ -60,7 +59,7 @@ func ensureDaemon() (*ipc.Client, error) {
 	}
 
 	// Compute the daemon binary path: same directory as the GUI binary.
-	daemonBin := filepath.Join(filepath.Dir(exe), "lmvpnd")
+	daemonBin := filepath.Join(filepath.Dir(exe), daemonBinaryName)
 	if _, err := os.Stat(daemonBin); err != nil {
 		return nil, fmt.Errorf("daemon binary not found at %s: %w", daemonBin, err)
 	}
@@ -69,20 +68,9 @@ func ensureDaemon() (*ipc.Client, error) {
 	uid := os.Getuid()
 	gid := os.Getgid()
 
-	// Launch the daemon via osascript (prompts for admin password).
-	// The `daemon-launch` subcommand forks lmvpnd with Setsid and exits
-	// immediately, so osascript returns right away.
-	script := fmt.Sprintf(
-		`do shell script %q with administrator privileges`,
-		fmt.Sprintf("%s daemon-launch --user-home %s --uid %d --gid %d --daemon-bin %s",
-			shellQuote(exe), shellQuote(home), uid, gid, shellQuote(daemonBin)),
-	)
-	cmd := exec.Command("osascript", "-e", script)
-	if out, err := cmd.CombinedOutput(); err != nil {
-		return nil, fmt.Errorf("launch daemon: %w (output: %s)", err, string(out))
+	if err := launchElevated(exe, daemonBin, home, uid, gid); err != nil {
+		return nil, err
 	}
-	log.L().Info("daemon launched via osascript",
-		"uid", uid, "gid", gid, "home", home, "daemon_bin", daemonBin)
 
 	// Wait for the daemon to become reachable.
 	logFile := paths.DaemonLogFile()
@@ -96,17 +84,4 @@ func ensureDaemon() (*ipc.Client, error) {
 	return nil, fmt.Errorf("daemon did not become reachable (check %s)", logFile)
 }
 
-// shellQuote wraps a string in single quotes for shell safety.
-// Embedded single quotes are escaped using the '\” pattern.
-func shellQuote(s string) string {
-	result := "'"
-	for _, r := range s {
-		if r == '\'' {
-			result += "'\\''"
-		} else {
-			result += string(r)
-		}
-	}
-	result += "'"
-	return result
-}
+