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Use tracks in jets only for sumpt2-driven vertex sorting: ATR-29435

Teng Jian Khoo requested to merge khoo/athena:24.0-Trig-FSVtxSumptw into 24.0

As an investigation for ATR-29435, this implements a tool that adapts the usual vertex sum(pt or pt2) calculation to be limited to tracks in jets -- with a customisable jet pt and dR matching cone.

This should be activated by setting

flags.Trigger.FSTrk.doJetRestrictedVertexSort = True

which is propagated to the vertexSortJetRestricted flag in the ID config flags.

It would be interesting to use this to study any changes in the compatibility between the HLT and offline vertexing under a change of this nature. However it is definitely CPU-suboptimal, because the tool interface has to build the set of jet-local tracks for every vertex. This could be solved in a couple of ways, but such optimisations could be left for when the performance is actually understood.

N.B. I have a mild concern that there might be cases where unresolved dependencies on the HLT EMTopo jets may arise depending on the menu -- some limited local testing, but it probably needs a bit of closer attention when the flag is activated.

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