[16.0.X] Add dummy implementation of edm::typeDemangle for standalone LST

[ariostas]

This PR adds a dummy implementation of edm::typeDemangle so that we don't have to link extra libraries when using the standalone version of LST. This is in response to #49953, where the dependency is introduced through PortableCollections.

This is a backport of #49964.

[cmsbuild]

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

It involves the following packages:

• RecoTracker/LSTCore (reconstruction)

@Moanwar, @cmsbuild, @jfernan2, @mandrenguyen, @srimanob can you please review it and eventually sign? Thanks.
@GiacomoSguazzoni, @VinInn, @VourMa, @dgulhan, @elusian, @felicepantaleo, @gpetruc, @mmasciov, @mmusich, @mtosi, @rovere 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 dummy implementation of edm::typeDemangle for standalone LST #49964

[cmsbuild]

cms-bot internal usage

[fwyzard]

please test

[fwyzard]

backport #49964

[cmsbuild]

+1

Size: This PR adds an extra 24KB to repository
Summary: https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-feaffe/50982/summary.html
COMMIT: c2310a7
CMSSW: CMSSW_16_0_X_2026-01-28-2300/el8_amd64_gcc13
User test area: For local testing, you can use /cvmfs/cms-ci.cern.ch/week0/cms-sw/cmssw/49971/50982/install.sh to create a dev area with all the needed externals and cmssw changes.

Comparison Summary

Summary:

• You potentially removed 2 lines from the logs
• Reco comparison results: 14 differences found in the comparisons
• DQMHistoTests: Total files compared: 55
• DQMHistoTests: Total histograms compared: 4382508
• DQMHistoTests: Total failures: 14
• DQMHistoTests: Total nulls: 0
• DQMHistoTests: Total successes: 4382474
• DQMHistoTests: Total skipped: 20
• DQMHistoTests: Total Missing objects: 0
• DQMHistoSizes: Histogram memory added: 0.0 KiB( 54 files compared)
• Checked 235 log files, 208 edm output root files, 55 DQM output files
• TriggerResults: found differences in 1 / 53 workflows

[fwyzard]

urgent

Needed by #49953

[mandrenguyen]

+1

[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_16_1_X is complete. This pull request will be automatically merged.