Add MLPF Producer

[kpedro88]

The MLPF algorithm has not been officially introduced in CMSSW yet. Implementation in a SonicTriton producer is likely the easiest path (especially for a PyTorch graph-based network, since the PyTorch C++ API is not yet available in CMSSW).

Particular considerations:

• Consider introducing ProcessModifier to enable the alternative sequence

Assigned to: @jpata

[kpedro88]

See: cms-sw/cmssw#32048

[srimanob]

@kpedro88 @jpata
Anything else to be done on this issue? Thanks.

[jpata]

The initial proof of concept MLPF producer was merged in cms-sw/cmssw#32048.

I'm working on a MLPF v2 training and PR for cmssw with the goal of reasonable downstream physics with the MLPF candidates in CMSSW. I think additional inference implementations i.e. Sonic could be a good technical follow-up to that. This may be a month or so from now.