Python: Create ensemble curve sets when creating summary plot for ensemble

new_summary_plot() with an ensemble and an address string created an empty
plot. The address filters were applied to an empty list of summary cases, and
no curve sets were created. Use the summary cases of the ensemble, and make
sure the summary addresses are created before the address filters are applied.

Add example script showing how to create summary plots for an ensemble.

ApplicationLibCode/ProjectDataModelCommands/RimcSummaryPlotCollection.cpp

@@ -30,6 +30,8 @@
 #include "RimSummaryPlot.h"
 #include "RimSummaryPlotCollection.h"
 
+#include "RifSummaryReaderInterface.h"
+
 #include "cafPdmAbstractFieldScriptingCapability.h"
 #include "cafPdmFieldScriptingCapability.h"
 
@@ -62,7 +64,15 @@ std::expected<caf::PdmObjectHandle*, QString> RimcSummaryPlotCollection_newSumma
     {
         if ( !addressStrings.empty() )
         {
-            newPlot = RicSummaryPlotFeatureImpl::createSummaryPlotForEnsemble( std::vector<RimSummaryCase*>(), m_ensemble, addressStrings );
+            auto summaryCases = m_ensemble->allSummaryCases();
+
+            // Summary addresses are created on demand, make sure they are available before applying address filters
+            for ( auto summaryCase : summaryCases )
+            {
+                if ( auto reader = summaryCase ? summaryCase->summaryReader() : nullptr ) reader->createAddressesIfRequired();
+            }
+
+            newPlot = RicSummaryPlotFeatureImpl::createSummaryPlotForEnsemble( summaryCases, m_ensemble, addressStrings );
         }
         else
         {