allow to (multi) select scrap

src/ui/SelectedBuildingPanel.h

@@ -18,6 +18,7 @@
 #include "GameConfig.h"
 #include "PlayerCommandsAppliedEvent.h"
 #include "RecipesConfig.h"
+#include "ScrapSelectionChangedEvent.h"
 #include "SelectionChangedEvent.h"
 #include "ShipLayout.h"
 #include "ShipsConfig.h"
@@ -37,6 +38,7 @@ class SelectedBuildingPanel : public QWidget,
                                                            PlayerCommandsAppliedEvent,
                                                            EntitySelectedEvent,
                                                            SelectionChangedEvent,
+                                                           ScrapSelectionChangedEvent,
                                                            DebugDrawToggledEvent>
 {
     Q_OBJECT
@@ -51,6 +53,7 @@ private:
     void handleEvent(std::shared_ptr<const PlayerCommandsAppliedEvent> event) override;
     void handleEvent(std::shared_ptr<const EntitySelectedEvent> event) override;
     void handleEvent(std::shared_ptr<const SelectionChangedEvent> event) override;
+    void handleEvent(std::shared_ptr<const ScrapSelectionChangedEvent> event) override;
     void handleEvent(std::shared_ptr<const DebugDrawToggledEvent> event) override;
 
 private slots:
@@ -77,6 +80,8 @@ private:
     void buildEmpty();
     void buildSingle(BuildingId id);
     void buildMulti(const std::vector<BuildingId>& ids);
+    void buildScrap();
+    void refreshScrapTotal();
     void refreshBuffers(const Building* b);
     void refreshSiteProgress(const ConstructionSite* s);
     void updateShipyardLayoutWidgets(BuildingType type,
@@ -115,6 +120,9 @@ private:
     QLabel*         m_entityTitleLabel;
     QLabel*         m_stationStatsLabel;
 
+    std::vector<entt::entity> m_selectedScrap;
+    QLabel*                   m_scrapLabel;
+
     void buildEntityShip(entt::entity entity);
     void buildEntityStation(entt::entity entity);
     void refreshEntityStats();