Keep dd4hep id as is from geant4 in muons
This replaces !1060 (closed) to avoid the fact that MR still see the original commits and differences from !979 (merged) after it was merged &s quashed.
See discussion there for Muons as it is needed to correctly apply hits to stations & regions.
For FT it may be needed due to how g4=dd4hep sensdetid is used: it may could be eventually passed along by dd4hep itself.