[axti98]

This PR implements a task that calculates the number of global tracks from the reduced datasets based on configurable track properties and with track-to-collision association. The default values for the global track definition are taken from https://aliceo2group.github.io/analysis-framework/docs/analysis-tools/TrackSelection.html. The common multiplicity estimator does not allow for this.

The task will later be updated to also calculate the multiplicity in azimuthal regions with respect to a ditrack / dielectron candidate. Also, removing the legs from the multiplicity is planned to be implemented in the future.

The multiplicity is estimated separately and made available in the VarManager, such that introducing event-selection cuts can be applied on that value.

Overview planned implementations:

• Estimate configurable MC multiplicity with particle composition correction (Exists in LF Framework)
• Estimate multiplicity in azimuthal regions of a ditrack / dielectron
• Configure to remove the decay daughters of the multiplicity
• Configure recalculation of DCA
• Use pT dependent DCAxy cut (resolution parameterization)

[github-actions]

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