AFT-702: Add heterogeneous input support for GN2

Idea:
Create an abstract class for a constituent loader with the getData function, which returns a vector of values. Each loader (e.g., TracksLoader, IParticlesLoader, ...) is inherited from it. Then, we have a vector of pointers and sequentially apply all of them and feed output to GNN. Relates to AFT-702

TO-DOs:

• Add abstract class for constituent loading
• Add tracksLoader class
• Add tracksLoader configuration
• Add IParticleLoader class
• Clean code

Tagging @dguest @svanstro @ioleksiy

changed the description

requested review from @svanstro, @dguest, and @nkakati

I'm not sure what "clean code" entails but I made some general comments. This is looking very good. Should we try running the CI?

Jenkins please retry a build

This merge request affects 1 package:

• PhysicsAnalysis/JetTagging/FlavorTagDiscriminants

This merge request affects 14 files:

• PhysicsAnalysis/JetTagging/FlavorTagDiscriminants/CMakeLists.txt
• PhysicsAnalysis/JetTagging/FlavorTagDiscriminants/FlavorTagDiscriminants/ConstituentsLoader.h
• PhysicsAnalysis/JetTagging/FlavorTagDiscriminants/FlavorTagDiscriminants/DataPrepUtilities.h
• PhysicsAnalysis/JetTagging/FlavorTagDiscriminants/FlavorTagDiscriminants/GNN.h
• PhysicsAnalysis/JetTagging/FlavorTagDiscriminants/FlavorTagDiscriminants/IParticlesLoader.h
• PhysicsAnalysis/JetTagging/FlavorTagDiscriminants/FlavorTagDiscriminants/SequenceGetter.h
• PhysicsAnalysis/JetTagging/FlavorTagDiscriminants/FlavorTagDiscriminants/SubjetsLoader.h
• PhysicsAnalysis/JetTagging/FlavorTagDiscriminants/FlavorTagDiscriminants/TracksLoader.h
• PhysicsAnalysis/JetTagging/FlavorTagDiscriminants/Root/DataPrepUtilities.cxx
• PhysicsAnalysis/JetTagging/FlavorTagDiscriminants/Root/GNN.cxx
• PhysicsAnalysis/JetTagging/FlavorTagDiscriminants/Root/IParticlesLoader.cxx
• PhysicsAnalysis/JetTagging/FlavorTagDiscriminants/Root/SequenceGetter.cxx
• PhysicsAnalysis/JetTagging/FlavorTagDiscriminants/Root/SubjetsLoader.cxx
• PhysicsAnalysis/JetTagging/FlavorTagDiscriminants/Root/TracksLoader.cxx

added Analysis BTagging JetEtmiss analysis-review-required main labels

CI Result FAILURE (hash 0b88b0d1)

	Athena	AnalysisBase	AthAnalysis
externals
cmake
make
tests

Full details available on this CI monitor view. Check the JIRA CI status board for known problems
Athena: number of compilation errors 0, warnings 1
AnalysisBase: number of compilation errors 0, warnings 1
AthAnalysis: number of compilation errors 0, warnings 1
For experts only: Jenkins output [CI-MERGE-REQUEST-EL9 4432]

added 2 commits

• 7e970fc8 - Clean code
• 72040228 - Remove redundant stuff

Compare with previous version