Mitigating GPU Moments Calculation Differences

By changing the algorithm that is used to calculate the eigenvalues and eigenvectors of the 3×3 matrix that gives the shower axis, we can improve the GPU-CPU differences, especially for Δα, Δφ and Δθ.

The new algorithm matches the non-iterative version used by Eigen, leveraging GPU intrinsics for better precision and performance.

This merge request affects 1 package:

• Calorimeter/CaloRecGPU

This merge request affects 2 files:

• Calorimeter/CaloRecGPU/src/GPUClusterInfoAndMomentsCalculatorImpl.cu
• Calorimeter/CaloRecGPU/src/GPUClusterInfoAndMomentsCalculatorImpl.h

Adding @dossantn ,@pavol as watchers

added CUDA Calorimeter main review-pending-level-1 labels

CI Result SUCCESS (hash 23d18665)

	Athena
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cmake
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Code changes look fine for me and the CI succeeded. Approving from L1 side.

removed review-pending-level-1 label

added review-approved label

merged

mentioned in commit 81cb33bf