Initial Bobink library: BobinkAuth, BobinkClient, and demo app

Implements the core OPC UA wrapper library with:
- Build system with automatic dep building (open62541, QtOpcUa)
- BobinkAuth: QML auth component (anonymous/userpass/certificate)
- BobinkClient: QML singleton managing connection, LDS discovery,
  PKI configuration, endpoint selection, and certificate trust flow
- Demo app for manual testing of the full connection flow

1 files changed, 18 insertions, 0 deletions

diff --git a/demo/main.cpp b/demo/main.cpp
new file mode 100644
index 0000000..de3c2fc
--- /dev/null
+++ b/demo/main.cpp
@@ -0,0 +1,18 @@
+#include <QGuiApplication>
+#include <QQmlApplicationEngine>
+
+int main(int argc, char *argv[])
+{
+    QCoreApplication::addLibraryPath(QStringLiteral(QTOPCUA_PLUGIN_PATH));
+
+    QGuiApplication app(argc, argv);
+    QQmlApplicationEngine engine;
+
+    QObject::connect(
+        &engine, &QQmlApplicationEngine::objectCreationFailed,
+        &app, []() { QCoreApplication::exit(1); },
+        Qt::QueuedConnection);
+
+    engine.loadFromModule("BobinkDemo", "Main");
+    return app.exec();
+}