Static cast safety.

Fixes https://gitlab.com/kicad/code/kicad/-/issues/20958

pcbnew/python/scripting/pcbnew_action_plugins.cpp

@@ -446,7 +446,7 @@ void PCB_EDIT_FRAME::RebuildAndRefresh()
 
     for( EDA_ITEM* item : selection.GetItems() )
     {
-        if( !item->IsSelected() )
+        if( !item->IsSelected() && item->IsBOARD_ITEM() )
             to_remove.push_back( static_cast<BOARD_ITEM*>( item ) );
     }
 

pcbnew/python/scripting/pcbnew_scripting_helpers.cpp

@@ -522,7 +522,8 @@ std::deque<BOARD_ITEM*> GetCurrentSelection()
         std::for_each( selection.begin(), selection.end(),
                        [&items]( EDA_ITEM* item )
                        {
-                           items.push_back( static_cast<BOARD_ITEM*>( item ) );
+                           if( item->IsBOARD_ITEM() )
+                               items.push_back( static_cast<BOARD_ITEM*>( item ) );
                        } );
     }