[16.0.X] add TestProcessor based tests for ScoutingCollectionMonitor

[mmusich]

backport of #50907

PR description:

From the original PR description

This PR is a follow-up to #50871 which stems from #50866.
This PR introduces a Catch2 test suite for ScoutingCollectionMonitor and improves the robustness of the edm::ValueMap retrieval in the analyze() method.
I provide TestProcessor-based tests that make sure there are no crashes when we run with missing input.
The Catch2 test binary is added with two test cases:

• "ScoutingCollectionMonitor" tests: exercises the standard lifecycle methods (testWithNoRuns, testBeginAndEndJobOnly, test, testRunWithNoLuminosityBlocks, testLuminosityBlockWithNoEvents) using the default _cfi configuration.
• "ScoutingCollectionMonitor invalid beamspot": specifically targets the code path where the beamspot handle is invalid. Since analyze() returns early when any mandatory collection handle is missing, all mandatory collections (muons, electrons, photons, PF jets, PF candidates, tracks, vertices, MET, rho, and all twelve electron best-track ValueMaps) are supplied as empty or default-constructed objects via TestProcessor::put, while the beamspot InputTag is pointed at a non-existent label. This verifies that the beamspot-guarded histogram fills (tk_BS_dxy, tk_BS_dz, trkd0BS, trkdzBS) are correctly skipped without crashing.

PR validation:

Run successfully the following unit tests:

scram b runtests_testScoutingCollectionMonitor
scram b runtests_TestDQMOnlineClient-scouting_dqm_sourceclient

If this PR is a backport please specify the original PR and why you need to backport that PR. If this PR will be backported please specify to which release cycle the backport is meant for:

verbatim backport of #50907 to the 2026 pp data-taking release.

[mmusich]

type ngt

[cmsbuild]

A new Pull Request was created by @mmusich for CMSSW_16_0_X.

It involves the following packages:

• DQM/HLTEvF (dqm, hlt)

@Martin-Grunewald, @cmsbuild, @ctarricone, @gabrielmscampos, @mmusich, @rseidita can you please review it and eventually sign? Thanks.
@missirol, @mtosi 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

• Backported from add TestProcessor based tests for ScoutingCollectionMonitor #50907

[cmsbuild]

cms-bot internal usage

[mmusich]

test parameters:

• addpkg = DQM/Integration

[mmusich]

@cmsbuild, please test

[cmsbuild]

+1

Size: This PR adds an extra 20KB to repository
Summary: https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-ea30bc/53263/summary.html
COMMIT: b4fe1ce
CMSSW: CMSSW_16_0_X_2026-05-10-0000/el8_amd64_gcc13
User test area: For local testing, you can use /cvmfs/cms-ci.cern.ch/week1/cms-sw/cmssw/50945/53263/install.sh to create a dev area with all the needed externals and cmssw changes.

Comparison Summary

Summary:

• You potentially removed 3 lines from the logs
• ROOTFileChecks: Some differences in event products or their sizes found
• Reco comparison results: 4 differences found in the comparisons
• DQMHistoTests: Total files compared: 53
• DQMHistoTests: Total histograms compared: 4172318
• DQMHistoTests: Total failures: 108
• DQMHistoTests: Total nulls: 0
• DQMHistoTests: Total successes: 4172190
• DQMHistoTests: Total skipped: 20
• DQMHistoTests: Total Missing objects: 0
• DQMHistoSizes: Histogram memory added: 0.0 KiB( 52 files compared)
• Checked 227 log files, 197 edm output root files, 53 DQM output files
• TriggerResults: no differences found

[mmusich]

+hlt

• verbatim backport of add TestProcessor based tests for ScoutingCollectionMonitor #50907

[gabrielmscampos]

+dqm

[cmsbuild]

This pull request is fully signed and it will be integrated in one of the next CMSSW_16_0_X IBs (tests are also fine) and once validation in the development release cycle CMSSW_17_0_X is complete. 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)