Add guarding tying to mitigate reported segmentation fault

2025-10-06 12:48:32.779] [rotating_logger] [error] Stack trace:
  [0] manageSegFailure(int) at :0
  [1]  at :0
  [2] __dynamic_cast at :0
  [3] RimSummaryMultiPlot::updateReadOutLines(double, double) at :0
  [4] CoordinatePicker::trackerText(QPoint const&) const at :0
  [5] QwtPicker::trackerRect(QFont const&) const at :0
  [6] QwtPicker::updateDisplay() at :0
  [7] QwtPicker::begin() at :0
  [8] QwtPicker::transition(QEvent const*) at :0
  [9] QwtPicker::eventFilter(QObject*, QEvent*) at :0
  [10] QCoreApplicationPrivate::sendThroughObjectEventFilters(QObject*, QEvent*) at :0
  [11] QApplicationPrivate::notify_helper(QObject*, QEvent*) at :0
  [12] RiaGuiApplication::notify(QObject*, QEvent*) at :0
  [13] QCoreApplication::notifyInternal2(QObject*, QEvent*) at :0
  [14]  at :0
  [15] QApplicationPrivate::sendMouseEvent(QWidget*, QMouseEvent*, QWidget*, QWidget*, QWidget**, QPointer<QWidget>&, bool, bool) at :0
  [16]  at :0
  [17]  at :0
  [18] QApplicationPrivate::notify_helper(QObject*, QEvent*) at :0
  [19] RiaGuiApplication::notify(QObject*, QEvent*) at :0
  [20] QCoreApplication::notifyInternal2(QObject*, QEvent*) at :0
  [21] QGuiApplicationPrivate::processMouseEvent(QWindowSystemInterfacePrivate::MouseEvent*) at :0
  [22] QWindowSystemInterface::sendWindowSystemEvents(QFlags<QEventLoop::ProcessEventsFlag>) at :0
  [23]  at :0
  [24] g_main_context_dispatch at :0
  [25] g_main_context_iterate.isra.20 at :0
  [26] g_main_context_iteration at :0
  [27] QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) at :0
  [28] QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) at :0
  [29] QCoreApplication::exec() at :0

ApplicationLibCode/ProjectDataModel/Summary/RimSummaryMultiPlot.cpp

@@ -1776,6 +1776,8 @@ void RimSummaryMultiPlot::updateReadOutLines( double qwtTimeValue, double yValue
 
     for ( auto plot : summaryPlots() )
     {
+        if ( !plot ) continue;
+
         if ( m_readOutSettings->enableVerticalLine() && plot->timeAxisProperties() )
         {
             plot->timeAxisProperties()->removeAllAnnotations();