add btn to show a particle composition in real space view

GUI/View/SampleDesigner/ParticleCompositionForm.cpp

@@ -47,6 +47,10 @@ ParticleCompositionForm::ParticleCompositionForm(QWidget* parent,
 
     auto* collapser = GroupBoxCollapser::installIntoGroupBox(this);
 
+    auto* showInRealSpaceAction = ActionFactory::createShowInRealSpaceAction(
+        this, "particle composition", [=] { ec->requestViewInRealSpace(compositionItem); });
+    collapser->addAction(showInRealSpaceAction);
+
     if (allowRemove) {
         m_removeAction = ActionFactory::createRemoveAction(
             this, "particle composition", [=] { ec->removeParticle(compositionItem); });