HomeHEPForge

Fix tricky object lifetime bug affecting WFinder users

Description

Fix tricky object lifetime bug affecting WFinder users

So far, taking a const reference to WFinder::constituentLepton() or
...Neutrino() was unsafe, since they internally rely on returning
a temporary value from the filter_select() tools which goes out of scope
immediately.

Projections need to store such temporaries themselves in member variables.