This is a first part of the CscOverlay
cleanup and modernisation
overlayContainer
as it was done for other muon overlay algorithms (see !21148 (merged) and !21454 (merged)).copyCollection
function.MAX_AMPL
to the anonymous namespace.mergeCollections
method will be fully cleaned up in a follow-up MR. Also all output-changing stuff will be changed later.
This MR should not change the output.