give the selection cards their own parts instead of label blobs

src/ui/selection/FieldMultiContent.h

@@ -7,7 +7,7 @@
 #include "SelectionContent.h"
 #include "SelectionContentFactory.h"
 
-class QLabel;
+class StatRow;
 
 // The count summary for a field selection holding more than one object that does not
 // aggregate (REQ-UI-FIELD-MULTI-SELECTION): several actors, or actors together with
@@ -24,7 +24,10 @@ protected:
     void refreshRuntime() override;
 
 private:
-    std::vector<entt::entity> m_actors;
+    void buildSummary(const std::vector<entt::entity>& actors);
+
     std::vector<entt::entity> m_debris;
-    QLabel*                   m_summaryLabel;
+    // Null unless debris is part of the selection; the only value here that changes
+    // while the selection stands.
+    StatRow*                  m_scrapRow;
 };