[G4]Update vecgeom v2.0.0-rc.8 and g4hepem 20251114

[smuzaffar]

backported vecgeom/g4hepem changes from #10198 (already integrated in G4ADEPT IBs)

[cmsbuild]

A new Pull Request was created by @smuzaffar for branch IB/CMSSW_16_0_X/g4.

@akritkbehera, @cmsbuild, @iarspider, @smuzaffar can you please review it and eventually sign? Thanks.
@ftenchini, @mandrenguyen, @sextonkennedy you are the release manager for this.
cms-bot commands are listed here

[cmsbuild]

cms-bot internal usage

[smuzaffar]

please test for CMSSW_16_0_G4VECGEOM_X

[smuzaffar]

+externals

good to go in special Geant4 IBs

[cmsbuild]

This pull request is fully signed and it will be integrated in one of the next IB/CMSSW_16_0_X/g4 IBs after it passes the integration tests. This pull request will now be reviewed by the release team before it's merged. @sextonkennedy, @ftenchini, @mandrenguyen (and backports should be raised in the release meeting by the corresponding L2)

[cmsbuild]

+1

Summary: https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-f7096a/49486/summary.html
COMMIT: 1d50d05
CMSSW: CMSSW_16_0_G4VECGEOM_X_2025-11-16-2300/el8_amd64_gcc13
User test area: For local testing, you can use /cvmfs/cms-ci.cern.ch/week0/cms-sw/cmsdist/10202/49486/install.sh to create a dev area with all the needed externals and cmssw changes.

The following merge commits were also included on top of IB + this PR after doing git cms-merge-topic:

• @pallabidas Updating EMTF NN to v1.0.1 #10191

You can see more details here:
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-f7096a/49486/git-recent-commits.json
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-f7096a/49486/git-merge-result

Comparison Summary

Summary:

• You potentially added 415 lines to the logs
• ROOTFileChecks: Some differences in event products or their sizes found
• Reco comparison results: 62436 differences found in the comparisons
• Reco comparison had 2 failed jobs
• DQMHistoTests: Total files compared: 51
• DQMHistoTests: Total histograms compared: 3896448
• DQMHistoTests: Total failures: 338210
• DQMHistoTests: Total nulls: 286
• DQMHistoTests: Total successes: 3557932
• DQMHistoTests: Total skipped: 20
• DQMHistoTests: Total Missing objects: 0
• DQMHistoSizes: Histogram memory added: -7.088999999999999 KiB( 50 files compared)
• DQMHistoSizes: changed ( 10224.0 ): -0.544 KiB SiStrip/MechanicalView
• DQMHistoSizes: changed ( 13034.0 ): -4.380 KiB SiStrip/MechanicalView
• DQMHistoSizes: changed ( 17034.0 ): 4.442 KiB SiStrip/MechanicalView
• DQMHistoSizes: changed ( 250202.181 ): 0.176 KiB SiStrip/MechanicalView
• DQMHistoSizes: changed ( 25202.0 ): -0.234 KiB SiStrip/MechanicalView
• DQMHistoSizes: changed ( 7.3 ): -5.771 KiB SiStrip/MechanicalView
• DQMHistoSizes: changed ( 8.0 ): -0.778 KiB SiStrip/MechanicalView
• Checked 218 log files, 188 edm output root files, 51 DQM output files
• TriggerResults: found differences in 16 / 49 workflows