MTD validation: add multiplicty plots for tracks selected for PV reconstruction

[fabiocos]

PR description:

Plots for the multiplicity of tracks selected for PV reconstruction, inclusive and with MTD information, inclusive and vs eta, are added to Primary4DVertexValidation.

PR validation:

code runs on RelVal samples and produces the desired histograms.

[cmsbuild]

cms-bot internal usage

[cmsbuild]

+code-checks

Logs: https://cmssdt.cern.ch/SDT/code-checks/cms-sw-PR-50564/48740

[cmsbuild]

A new Pull Request was created by @fabiocos for master.

It involves the following packages:

• Validation/MtdValidation (dqm)

@cmsbuild, @ctarricone, @gabrielmscampos, @nothingface0, @rseidita can you please review it and eventually sign? Thanks.
@martinamalberti this is something you requested to watch as well.
@ftenchini, @mandrenguyen, @sextonkennedy you are the release manager for this.

cms-bot commands are listed here

[fabiocos]

please test

[fabiocos]

@prabhatsolanki FYI

[cmsbuild]

+1

Size: This PR adds an extra 52KB to repository
Summary: https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-beae27/52294/summary.html
COMMIT: 666aa4a
CMSSW: CMSSW_16_1_X_2026-03-26-1100/el8_amd64_gcc13
User test area: For local testing, you can use /cvmfs/cms-ci.cern.ch/week0/cms-sw/cmssw/50564/52294/install.sh to create a dev area with all the needed externals and cmssw changes.

Comparison Summary

Summary:

• You potentially removed 6 lines from the logs
• Reco comparison results: 4 differences found in the comparisons
• DQMHistoTests: Total files compared: 53
• DQMHistoTests: Total histograms compared: 4186890
• DQMHistoTests: Total failures: 144
• DQMHistoTests: Total nulls: 0
• DQMHistoTests: Total successes: 4186726
• DQMHistoTests: Total skipped: 20
• DQMHistoTests: Total Missing objects: 0
• DQMHistoSizes: Histogram memory added: 6.9350000000000005 KiB( 52 files compared)
• DQMHistoSizes: changed ( 34434.0,... ): 1.387 KiB MTD/Vertices
• Checked 227 log files, 198 edm output root files, 53 DQM output files
• TriggerResults: no differences found

[gabrielmscampos]

+dqm

[cmsbuild]

This pull request is fully signed and it will be integrated in one of the next master IBs (tests are also fine). This pull request will now be reviewed by the release team before it's merged. @sextonkennedy, @mandrenguyen, @ftenchini (and backports should be raised in the release meeting by the corresponding L2)