Import: DXF parser/imported improve unsupported features count

Classify unsupported features by type, and report on
the breakdown.

src/Mod/Import/App/dxf/ImpExpDxf.cpp

@@ -1384,7 +1384,6 @@ Py::Object ImpExpDxfRead::getStatsAsPyObject()
     statsDict.setItem("finalScalingFactor", Py::Float(m_stats.finalScalingFactor));
     statsDict.setItem("importTimeSeconds", Py::Float(m_stats.importTimeSeconds));
     statsDict.setItem("totalEntitiesCreated", Py::Long(m_stats.totalEntitiesCreated));
-    statsDict.setItem("unsupportedFeaturesCount", Py::Long(m_stats.unsupportedFeaturesCount));
 
     Py::Dict entityCountsDict;
     for (const auto& pair : m_stats.entityCounts) {
@@ -1398,5 +1397,11 @@ Py::Object ImpExpDxfRead::getStatsAsPyObject()
     }
     statsDict.setItem("importSettings", importSettingsDict);
 
+    Py::Dict unsupportedFeaturesDict;
+    for (const auto& pair : m_stats.unsupportedFeatures) {
+        unsupportedFeaturesDict.setItem(pair.first.c_str(), Py::Long(pair.second));
+    }
+    statsDict.setItem("unsupportedFeatures", unsupportedFeaturesDict);
+
     return statsDict;
 }

src/Mod/Import/App/dxf/dxf.cpp

@@ -2397,9 +2397,9 @@ bool CDxfRead::SkipBlockContents()
 template<typename... args>
 void CDxfRead::UnsupportedFeature(const char* format, args&&... argValuess)
 {
-    m_stats.unsupportedFeaturesCount++;
     // NOLINTNEXTLINE(runtime/printf)
     std::string formattedMessage = fmt::sprintf(format, std::forward<args>(argValuess)...);
+    m_stats.unsupportedFeatures[formattedMessage]++;
     // We place these formatted messages in a map, count their occurrences and not their first
     // occurrence.
     if (m_unsupportedFeaturesNoted[formattedMessage].first++ == 0) {

src/Mod/Import/App/dxf/dxf.h

@@ -187,8 +187,8 @@ struct DxfImportStats
     double finalScalingFactor = 1.0;
     std::map<std::string, int> entityCounts;
     std::map<std::string, std::string> importSettings;
+    std::map<std::string, int> unsupportedFeatures;
     int totalEntitiesCreated = 0;
-    int unsupportedFeaturesCount = 0;
 };