Be more pedantic about RECURSE_MODE.

Also fixes an invalid iterator bug.

Also adds mirroring support for PCB_GROUPs.

Fixes https://gitlab.com/kicad/code/kicad/-/issues/21107

eeschema/tools/sch_edit_tool.cpp

@@ -1530,7 +1530,7 @@ int SCH_EDIT_TOOL::RepeatDrawItem( const TOOL_EVENT& aEvent )
         {
             if( newItem->IsGroupableType() )
             {
-                commit.Modify( enteredGroup );
+                commit.Modify( enteredGroup, m_frame->GetScreen(), RECURSE_MODE::NO_RECURSE );
                 enteredGroup->AddItem( newItem );
             }
         }