feat(util): Grid type-erased output and comparisons

[paulgessinger]

• Concrete Axis instances get an outstream operator
  • IAxis adds a toStream virtual method overriden by derived classes, so IAxis instances become printable without downcasting.
• IGrid also gets a toStream virtual method + an outstream operator to allow printing a whole grid.
• IAxis gets an equality operator
• IGrid gets an equality operator working with the IAxis interface instead of dedicated virtual methods. This only checks the axes for equivalence, not the grid contents
• Adds a minimal AxisConcept class, that just checks if a type inherits from IAxis.
• IAxis gets a visit function accepting a generic callable. This function will use runtime control flow to call the callable with the concrete axis type. This allows dispatching into code with the correct concrete axis type, without having to copy the downcasting logic everywhere:

  const IAxis& someAxis;
  someAxis.visit([](auto axis) {
    // decltype(axis) is now the concrete axis type. 
  });

I think this functionality is somewhat related, which is why I grouped it like this. If there's disagreement, I'm happy to split this up further.

[andiwand]

LGTM 👍 left two minor comments

[github-actions]

📊: Physics performance monitoring for 6403bc9

Full contents

physmon summary

• ✅ CKF truth_smeared
• ✅ IVF truth_smeared
• ✅ AMVF truth_smeared
• ✅ Track Summary CKF truth_smeared
• ✅ Seeding truth_estimated
• ✅ CKF truth_estimated
• ✅ IVF truth_estimated
• ✅ AMVF truth_estimated
• ✅ Track Summary CKF truth_estimated
• ✅ Seeding seeded
• ✅ CKF seeded
• ✅ IVF seeded
• ✅ AMVF seeded
• ✅ AMVF (+grid seeder) seeded
• ✅ Track Summary CKF seeded
• ✅ Seeding orthogonal
• ✅ CKF orthogonal
• ✅ IVF orthogonal
• ✅ AMVF orthogonal
• ✅ Track Summary CKF orthogonal
• ✅ Ambisolver seeded
• ✅ Ambisolver orthogonal
• ✅ Seeding ttbar
• ✅ CKF ttbar
• ✅ Ambisolver
• ✅ Track Summary CKF ttbar
• ✅ AMVF ttbar
• ✅ AMVF (+grid seeder) ttbar
• ✅ Particles ttbar
• ✅ Vertices ttbar
• ✅ Truth tracking (GSF)
• ✅ Truth tracking
• ✅ Truth tracking (GX2F)
• ✅ Particles fatras
• ✅ Particles geant4

[asalzburger]

Looks good.

[asalzburger]

The new code looks all tested, so I guess SonarCloud reports a bit awkwardly here?

[paulgessinger]

@asalzburger I can add some more test for the output and equality code. Doesn't hurt anyway.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
42.1% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud

[acts-project-service]

🔴 Athena integration test results [727d4b1]

🔴 Some tests have failed!

Please investigate the pipeline!

status	job	report
🟢	report_pull_request
🟢	run_art_test: test_data18_13TeV_1000evt
🟢	run_art_test: test_ttbarPU40_reco
🟢	test_ActsDumpGeometryIdentifiers
🔴	test_ActsCheckObjectCountsCachedWorkflow
🔴	test_ActsCheckObjectCountsWorkflow
🟢	test_ActsEFTrackFit
🟢	test_ActsPersistifySeeds
🟢	test_ActsBenchmarkWithSpot
🟢	test_ActsAnalogueClustering
🟢	test_ActsWorkflowHeavyIons
🟢	test_ActsWorkflowFastTracking
🟢	test_ActsWorkflowCached
🟢	test_ActsWorkflow
🟢	test_ActsValidateAmbiguityResolution
🟢	test_ActsValidateResolvedTracks
🟢	test_ActsValidateTracks
🟢	test_ActsValidateActsCoreSpacePoints
🟢	test_ActsValidateActsSpacePoints
🟢	test_ActsValidateSeeds
🟢	test_ActsValidateOrthogonalSeeds
🟢	test_ActsValidateClusters
🟢	test_ActsPersistifyEDM
🟢	test_ActsGSFRefitting
🟢	test_ActsKfRefitting
🟢	test_ActsExtrapolationAlgTest
🟢	test_ActsITkTest
🟢	run_workflow_tests_run4_mc
🟢	run_workflow_tests_run2_mc
🟢	run_workflow_tests_run2_data
🟢	run_workflow_tests_run3_mc
🟢	run_workflow_tests_run3_data
🟢	run_unit_tests