[labs.dla 4] Cartan decomposition

[Qottmann]

Simple implementation of a cartan_decomposition function that takes in a set of operators and an appropriate involution function that maps the input operator types to a binary output classifying them into the even and odd parity subspaces.

This implicitly assumes that all input operators are in either space already (hence a simple implementation of the Cartan decomposition.

[sc-74995]
[sc-76116]

[github-actions]

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[codecov]

Codecov Report

Attention: Patch coverage is 0% with 23 lines in your changes missing coverage. Please review.

Project coverage is 99.18%. Comparing base (814e991) to head (6e889ab).
Report is 57 commits behind head on structure_constants_dense.

Files with missing lines	Patch %	Lines
pennylane/labs/dla/cartan.py	0.00%	22 Missing ⚠️
pennylane/labs/dla/__init__.py	0.00%	1 Missing ⚠️

Additional details and impacted files

@@                      Coverage Diff                      @@
##           structure_constants_dense    #6392      +/-   ##
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- Coverage                      99.39%   99.18%   -0.22%     
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  Files                            448      452       +4     
  Lines                          42471    42556      +85     
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- Hits                           42216    42211       -5     
- Misses                           255      345      +90     

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