[QoL] Add ROOT CLI compatibility for GeomUtils + macro for single det overlaps check

Quite straightforward, just copying the logic used for the McbmUtils
Found because needed to make a macro for "single geo overlap checks", but should be useful in general to just have all these available (almost) transparently in ROOT (as for the McbmUtils, one need two extra lines creating an empty instance of the dummy class ToForceLibLoad to get it loaded)

The macro is mostly similar to the one for the full setups (check_overlaps.C) on which it is based, but inherits more TopNode loading/detection options from scan_geom.C
=> I suspect that it would be incompatible with full setup geo files and therefore I did not attempt to merge them, as it was not worth the effort (two working macros with proper names for separate case)

Ready but not pressing/urgent, created the MR mainly to cleanup my local git folder and make it easier to reference if somebody need the "single geo overlap checks" macro during MR reviews

added Build System Geometry core labels

requested review from @e.clerkin

assigned to @f.uhlig

Nothing in the README.

Nothing in file to say it is mcbm specific?

Don't see why we need a separate macro for this.

There should be just one general macro for overalps, both as single detectors and the whole system.

Can you update existing?

Could be that it works, however the geometry are not loaded in the same way: in one case we rely on the CbmSetup infrastructure with its interface over a few lines, in the other it is the longer parts I copied from your scan_geometry macro and some GeomUtils functions.

I confess that I did not try to check if this could be combined in a clean way in a single macro, as this was created a few months ago during the beamtime rush while trying to prepare the mMUCH or mTRD geometry (forgot which one of the two, the problems was that it was already merged and only weeks later added to a setup), so I did not want to invest more time on it

Dear @f.uhlig, @v.friese, @p.-a.loizeau,

you have been identified as code owner of at least one file which was changed with this merge request.

Please check the changes and approve them or request changes.

added CodeOwners label

added 80 commits

• 69722102...6224b9f7 - 77 commits from branch computing:master
• a717c899 - Add ROOT CLI compatibility for GeomUtils, needed for single geo overlap checks
• 857f91b6 - Add macro to check overlaps in a single detector geometry file
• fd5416cd - Add description of new macro in Geometry macros README

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Stopped the pipeline as only part of the threads were addressed