New geometry implementation

[jbeirer]

This pull request fully redesigns the way we handle the gometry in FastCaloSim, especially the hit to cell matching. Previously, complex detector maps were built that allowed for a fast cell lookup based on the η-φ and x-y (FCAL) positions. This has in many cases a direct dependence on the ATLAS geometry. Now, the cell data is loaded into RTree's (one per layer) that allow for a fast cell lookup given a position in the detector. This massively simplifies the geometry handling. Simulation remains largely unchanged, but some differences are unavoidable:

• in the old implementation, the extrapolation used information based on average cell dimensions in a single layer (e.g. averaged over φ). Now, we directly use the information of the best machting cell, which in principle should be more accurate.
• Due to a Athena bug (https://its.cern.ch/jira/browse/ATLASRECTS-7085) the cell dimensions for TileGap3 (17) are slightly different, even thoug the same Run 2 geo tag is used

As expected, the R-tree lookup is significantly slower $O(\log(n))$ than the old approach (x100), but this is not expected to become a bottleneck:

The hit-to-cell matching assumes regular cuboid cells. If this approximation is not sufficient or experiments want to implement a faster lookup such as for the ATLAS FCal, this can be done via setting alternative geo handlers to the geometry:

// Create alternative geometry handler for FCal
std::shared_ptr<FCal> fcal_geo = std::make_shared<FCal>();
// Load the FCal geometry from the files
fcal_geo->load(AtlasGeoTestsConfig::FCAL_ELECTRODE_FILES);
// Cast the FCal geometry handler to the geo interface
std::shared_ptr<CaloGeo> fcal_geo_handler =
std::static_pointer_cast<CaloGeo>(fcal_geo);
// Set the alternative geometry handler for the FCal layers (21 - 23)
geo->set_alt_geo_handler(21, 23, fcal_geo_handler);

Currently we use an std::map for mapping the cell id to the energy depositions to be able to have a consistent CI comparison. This will change to std::unorderd_map to allow for faster average lookup times of $O(1)$.

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 84.74903% with 79 lines in your changes missing coverage. Please review.

Project coverage is 36.48%. Comparing base (d58256e) to head (4a758b5). Report is 1 commits behind head on main.

:white_check_mark: All tests successful. No failed tests found.

Files with missing lines	Patch %	Lines
include/FastCaloSim/Geometry/Cell.h	51.42%	17 Missing :warning:
source/Core/TFCSExtrapolationState.cxx	7.14%	13 Missing :warning:
source/Geometry/CaloGeo.cxx	87.96%	13 Missing :warning:
source/Core/TFCSPredictExtrapWeights.cxx	0.00%	12 Missing :warning:
include/FastCaloSim/Geometry/FCal.h	94.21%	7 Missing :warning:
...ce/Core/TFCSLateralShapeParametrizationHitBase.cxx	0.00%	4 Missing :warning:
source/Core/TFCSEnergyAndHitGANV2.cxx	0.00%	3 Missing :warning:
source/Core/TFCSHitCellMappingFCal.cxx	83.33%	2 Missing :warning:
source/Core/TFCSSimulationState.cxx	66.66%	2 Missing :warning:
include/FastCaloSim/Core/TFCSEnergyAndHitGANV2.h	0.00%	1 Missing :warning:
... and 5 more

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #35 +/- ## ========================================== - Coverage 38.54% 36.48% -2.07% ========================================== Files 223 211 -12 Lines 10641 9476 -1165 Branches 1516 1334 -182 ========================================== - Hits 4102 3457 -645 + Misses 6539 6019 -520 ```

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