Add JettingProxy relay, convert Xpl2Client to active connection modelHEADmaster

Insert a transparent TCP proxy between the controller and N clients:
- JettingProxy listens on 9110-9112 (controller) and 9210-9212 (clients)
- Broadcasts controller frames to all clients, forwards client→controller
- Independent KA_PING handling on both sides

Convert Xpl2Client from passive QTcpServer listener to active QTcpSocket
outbound connections with auto-retry. New QML API: host/commandPort
properties, connectToProxy()/disconnectFromProxy() replacing
startListening()/stopListening().

1 files changed, 37 insertions, 0 deletions

diff --git a/jetting-proxy/main.cpp b/jetting-proxy/main.cpp
new file mode 100644
index 0000000..0e14054
--- /dev/null
+++ b/jetting-proxy/main.cpp
@@ -0,0 +1,37 @@
+/**
+ * @file   main.cpp
+ * @brief  Jetting proxy — relay between one controller and N clients.
+ */
+#include "JettingProxy.h"
+
+#include <QCommandLineParser>
+#include <QCoreApplication>
+
+int
+main (int argc, char *argv[])
+{
+  qSetMessagePattern ("Proxy      [%{time HH:mm:ss.zzz}] %{message}");
+
+  QCoreApplication app (argc, argv);
+
+  QCommandLineParser parser;
+  parser.addOption ({ "wire-debug", "Log forwarded frames to dev log" });
+  parser.addOption ({ "controller-port",
+                      "Base port for controller side (default 9110)", "port",
+                      "9110" });
+  parser.addOption ({ "client-port",
+                      "Base port for client side (default 9210)", "port",
+                      "9210" });
+  parser.addHelpOption ();
+  parser.process (app);
+
+  if (parser.isSet ("wire-debug"))
+    JettingProxy::enableWireDebug ();
+
+  quint16 controllerPort = parser.value ("controller-port").toUShort ();
+  quint16 clientPort = parser.value ("client-port").toUShort ();
+
+  new JettingProxy (controllerPort, clientPort, &app);
+
+  return app.exec ();
+}