Make add virtual and add to common base so that both GeoPhysVol and GeoFullPhysVol can be used as envelopes

Follow-up from !141 (closed)

When investigating the possibility to use the existing GeoModelXml "Envelope" mechanism to insert new service material inside an existing volume (in this case to position ITk/HGTD service material in the Calorimeter crack region) it was noticed that the mechanism only works for GeoPhysVols while the specific location where new items would ideally be inserted is a GeoFullPhysVol. This MR adds the capability to also use a GeoFullPhysVol as an Envelope, through making the add(GeoGraphNode* graphNode) method a virtual method of the common base class used by both GeoPhysVol and GeoFullPhysVol, i.e. GeoVPhysVol.

FYI @boudreau @mbandier @dellacqu

approved this merge request

Hi @nstyles , Many thanks for this MR! We (@boudreau , @tsulaia and I) discussed it today and it looks good. Going to merge it.

Cheers, Marilena

mentioned in commit fd76d7dd

merged

resolved all threads

mentioned in merge request atlas/athena!56574 (merged)

mentioned in issue #43

mentioned in merge request atlas/athena!56642 (merged)