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, 73 insertions, 0 deletions

diff --git a/src/BobinkAuth.cpp b/src/BobinkAuth.cpp
new file mode 100644
index 0000000..fed1da2
--- /dev/null
+++ b/src/BobinkAuth.cpp
@@ -0,0 +1,73 @@
+#include "BobinkAuth.h"
+
+BobinkAuth::BobinkAuth(QObject *parent)
+    : QObject(parent)
+{
+}
+
+BobinkAuth::AuthMode BobinkAuth::mode() const { return m_mode; }
+
+void BobinkAuth::setMode(AuthMode mode)
+{
+    if (m_mode == mode)
+        return;
+    m_mode = mode;
+    emit modeChanged();
+}
+
+QString BobinkAuth::username() const { return m_username; }
+
+void BobinkAuth::setUsername(const QString &username)
+{
+    if (m_username == username)
+        return;
+    m_username = username;
+    emit usernameChanged();
+}
+
+QString BobinkAuth::password() const { return m_password; }
+
+void BobinkAuth::setPassword(const QString &password)
+{
+    if (m_password == password)
+        return;
+    m_password = password;
+    emit passwordChanged();
+}
+
+QString BobinkAuth::certPath() const { return m_certPath; }
+
+void BobinkAuth::setCertPath(const QString &path)
+{
+    if (m_certPath == path)
+        return;
+    m_certPath = path;
+    emit certPathChanged();
+}
+
+QString BobinkAuth::keyPath() const { return m_keyPath; }
+
+void BobinkAuth::setKeyPath(const QString &path)
+{
+    if (m_keyPath == path)
+        return;
+    m_keyPath = path;
+    emit keyPathChanged();
+}
+
+QOpcUaAuthenticationInformation BobinkAuth::toAuthenticationInformation() const
+{
+    QOpcUaAuthenticationInformation info;
+    switch (m_mode) {
+    case Anonymous:
+        info.setAnonymousAuthentication();
+        break;
+    case UserPass:
+        info.setUsernameAuthentication(m_username, m_password);
+        break;
+    case Certificate:
+        info.setCertificateAuthentication(m_certPath, m_keyPath);
+        break;
+    }
+    return info;
+}