Digicontext: Several improvements

[sawenzel]

Work needed for restructuring O2DPG MC workflows towards the use of a globally pre-generated collision context.

• fixes for picking up vertices from collision contexts
• possibility to generate vertices in CollContextTool from CCDB entry
• smaller cleanup

relates to https://its.cern.ch/jira/browse/O2-3622

[github-actions]

REQUEST FOR PRODUCTION RELEASES:
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The following labels are available
async-2023-pbpb-apass4
async-2023-pp-apass4
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async-2024-PbPb-cpass0
async-2024-PbPb-apass1
async-2024-ppRef-apass1

[alibuild]

Error while checking build/O2/fullCI for e4bac82 at 2024-11-10 21:27:

## sw/BUILD/Clang-latest/log
  141 |   ExitOnError ExitOnErr(std::string(*argv[0]) + ": error:");
  201 |   ExitOnError ExitOnErr(std::string(*argv[0]) + ": error:");


## sw/BUILD/o2codechecker-latest/log
100% tests passed, 0 tests failed out of 1


## sw/BUILD/xjalienfs-latest/log
ERROR: pip's dependency resolver does not currently take into account all the packages that are installed. This behaviour is the source of the following dependency conflicts.


## sw/BUILD/O2-latest/log
c++: error: unrecognized command-line option '--rtlib=compiler-rt'
c++: error: unrecognized command-line option '--rtlib=compiler-rt'


## sw/BUILD/O2-full-system-test-latest/log
command alien-token-init had nonzero exit code 2


## sw/BUILD/o2checkcode-latest/log
--
========== List of errors found ==========
++ GRERR=0
++ grep -v clang-diagnostic-error error-log.txt
++ grep ' error:'
++ GRERR=1
++ [[ 1 == 0 ]]
++ mkdir -p /sw/INSTALLROOT/ba13b93db08338ac0aa8aed211fd6dee02e60677/slc8_x86-64/o2checkcode/1.0-local227/etc/modulefiles
++ cat
--

Full log here.