Add experimental metrics package following the array API standard

[fcogidi]

PR Type

Feature.

Short Description

Add new (experimental) metrics package with following features:

• Cross-framework support based on the Array API Standard.
• Distributed metric computation, including synchronization of metric state across multiple devices. Supported backend include mpi4py and torch.distributed.

Tests Added

• tests/cyclops/evaluate/metrics/experimental/test_metric.py
• tests/cyclops/evaluate/metrics/experimental/utils/test_ops.py
• tests/cyclops/evaluate/metrics/experimental/utils/test_validation.py
• tests/cyclops/evaluate/metrics/experimental/test_confusion_matrix.py

[codecov]

Codecov Report

Merging #499 (b80384a) into main (02c7e8c) will increase coverage by 1.40%.
Report is 4 commits behind head on main.
The diff coverage is 78.22%.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #499      +/-   ##
==========================================
+ Coverage   62.30%   63.70%   +1.40%     
==========================================
  Files          87       96       +9     
  Lines        8454     9409     +955     
==========================================
+ Hits         5267     5994     +727     
- Misses       3187     3415     +228     

Files	Coverage Δ
cyclops/utils/optional.py	100.00% <100.00%> (ø)
.../evaluate/metrics/experimental/confusion_matrix.py	98.80% <98.80%> (ø)
...perimental/distributed_backends/non_distributed.py	85.71% <85.71%> (ø)
...lops/evaluate/metrics/experimental/utils/typing.py	85.71% <85.71%> (ø)
.../metrics/experimental/distributed_backends/base.py	88.46% <88.46%> (ø)
.../evaluate/metrics/experimental/utils/validation.py	84.44% <84.44%> (ø)
...etrics/experimental/functional/confusion_matrix.py	89.47% <89.47%> (ø)
...etrics/experimental/distributed_backends/mpi4py.py	36.73% <36.73%> (ø)
...rimental/distributed_backends/torch_distributed.py	32.69% <32.69%> (ø)
cyclops/evaluate/metrics/experimental/metric.py	82.68% <82.68%> (ø)
... and 1 more

... and 9 files with indirect coverage changes