feat(portscanner): implement port scanning CLI and core logic

Implement command-line interface for port scanning with IP validation and option
parsing. Add core scanning logic using Boost.Asio for asynchronous socket
checks, including timeout handling and port probing. Update xmake.lua to
configure build target and include necessary files.

src/cli/portscan_cli.cpp

@@ -0,0 +1,26 @@
+#include "portscan_cli.hpp"
+#include <boost/program_options/value_semantic.hpp>
+#include <cassert>
+
+PortScanCli::PortScanCli()
+    : CliBase("Port Scanner Options")
+    , ip_("")
+{
+}
+
+void PortScanCli::setupOptions()
+{
+    // clang-format off
+    desc_.add_options()
+        ("help,h",     "Show help")
+        ("ip,H",       withDefault(ip_, "<IP>"),    "Local IPv4 to scan");
+    // clang-format on
+}
+
+std::string PortScanCli::getIp() const
+{
+    if (vm_["ip"].empty() == 0) {
+        return "127.0.0.1";
+    }
+    return vm_.at("ip").as<std::string>();
+}

src/cli/portscan_cli.hpp

@@ -0,0 +1,19 @@
+#pragma once
+
+#include "cli_base.hpp"
+#include "option_utils.hpp"
+#include <string>
+
+class PortScanCli : public CliBase, protected OptionUtils
+{
+  public:
+    PortScanCli();
+
+    std::string getIp() const;
+
+  protected:
+    void setupOptions() override;
+
+  private:
+    std::string ip_;
+};