Guards against null summary reader

Addresses potential null pointer dereferences by adding checks for null summary readers before accessing their data.

This change prevents crashes and improves the robustness of summary data processing, particularly when dealing with incomplete or corrupted summary data.

The checks are added in the following locations:
- RiaSummaryPlotTemplateTools
- RiaSummaryStringTools
- RicPlotProductionRateFeature
- RicSummaryPlotFeatureImpl
- RimAnalysisPlot
- RimSummaryCalculation
- RimEnsembleCurveFilter
- RimEnsembleCurveSet
- RimSummaryEnsemble
- RimSummaryMultiPlot
- RimSummaryRegressionAnalysisCurve
- RimSummaryEnsembleSumo

ApplicationLibCode/ProjectDataModel/AnalysisPlots/RimAnalysisPlot.cpp

@@ -244,6 +244,11 @@ std::set<RifEclipseSummaryAddress> RimAnalysisPlot::unfilteredAddresses() const
 
     for ( RimSummaryCase* sumCase : analyserOfSelectedCurveDefs->m_singleSummaryCases )
     {
+        if ( !sumCase || !sumCase->summaryReader() )
+        {
+            continue;
+        }
+
         const std::set<RifEclipseSummaryAddress>& caseAddrs = sumCase->summaryReader()->allResultAddresses();
         addresses.insert( caseAddrs.begin(), caseAddrs.end() );
     }