Draft: Add patches to VecGeom for clang19 and use VecCore 0.8.2 instead also for clang19
This MR introduces the following patch the VecGeom to work with clang19:
- patch VecGeom for clang19 compilation - the patch is copied from lcgcmake
- Use VecCore 0.8.2 instead also for clang19
I've made a full AtlasExternals+Athena build and ran all ctest+CITests - the build works fine and there are no CITest changes for simulation. The AthSimulationExternals+AthSimulation build also works fine, but there are reference files differences for CITest_SimulationRun3FullSimChecks_ctest
and subsequently CITest_SimulationRun3HitsMergeWithSort_ctest
Edited by Johannes Elmsheuser