Use session D-Bus for ukui ScreenSaver connections

Replace QDBusConnection::systemBus() with QDBusConnection::sessionBus()
when creating the org.ukui.ScreenSaver interface and connecting
Lock/Unlock signals so notifications are tied to the user session

src/screenlockdetector.cpp

@@ -204,7 +204,7 @@ bool ScreenLockDetector::connectToUkuiManager()
         "org.ukui.ScreenSaver",
         sessionPath,
         "org.ukui.ScreenSaver",
-        QDBusConnection::systemBus(),
+        QDBusConnection::sessionBus(),
         this
     );
 
@@ -212,7 +212,7 @@ bool ScreenLockDetector::connectToUkuiManager()
         qDebug() << "ukui ScreenSaver interface is valid for session:" << sessionPath;
 
         // 连接Lock和Unlock信号到特定会话
-        bool lockConnected = QDBusConnection::systemBus().connect(
+        bool lockConnected = QDBusConnection::sessionBus().connect(
             "org.ukui.ScreenSaver",
             sessionPath,
             "org.ukui.ScreenSaver",
@@ -221,7 +221,7 @@ bool ScreenLockDetector::connectToUkuiManager()
             SLOT(onSessionLocked())
         );
 
-        bool unlockConnected = QDBusConnection::systemBus().connect(
+        bool unlockConnected = QDBusConnection::sessionBus().connect(
             "org.ukui.ScreenSaver",
             sessionPath,
             "org.ukui.ScreenSaver",
@@ -469,4 +469,4 @@ void ScreenLockDetector::onSessionUnlocked()
     setLockState(false);
 }
 
-#endif // Q_OS_LINUX
+#endif // Q_OS_LINUX