deselect build tool when it becomes unaffordable and fix stale enabled button

src/ui/MainWindow.h

@@ -6,7 +6,6 @@
 
 #include <QWidget>
 
-#include "BuildingBlocksChangedEvent.h"
 #include "BuildingId.h"
 #include "EscapeMenuRequestedEvent.h"
 #include "EventHandler.h"
@@ -32,8 +31,7 @@ class QCloseEvent;
 class QResizeEvent;
 
 class MainWindow : public QWidget,
-                   public CombinedEventHandler<BuildingBlocksChangedEvent,
-                                               SchematicChoicesAvailableEvent,
+                   public CombinedEventHandler<SchematicChoicesAvailableEvent,
                                                GameOverEvent,
                                                WinEvent,
                                                EscapeMenuRequestedEvent,
@@ -52,7 +50,6 @@ protected:
     void closeEvent(QCloseEvent* event) override;
 
 private:
-    void handleEvent(std::shared_ptr<const BuildingBlocksChangedEvent> event) override;
     void handleEvent(std::shared_ptr<const SchematicChoicesAvailableEvent> event) override;
     void handleEvent(std::shared_ptr<const GameOverEvent> event) override;
     void handleEvent(std::shared_ptr<const WinEvent> event) override;