Add explicit serialization support for Obs and Ops binding classes for H distribution

[mlxd]

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Context: This PR adds explicit support for serialization and pickling of C++ bound classes in the Lightning backends. Additional functionality is added to validate this supports with scaled distribution of the pickled work using mpi4py.

Description of the Change: Enables explicit pickling support to C++ bound classes. Unlocks support for mpi4py concurrent futures API evaluation of pickled classes with forward pass and adjoint gradients of H.

Benefits: Allows immediate scaling evaluations of forward pass and adjoint gradients of Hamiltonians with LightningKokkos.

Possible Drawbacks: Functionality integration requires subtle architectural changes to better integrate with other backends in ecosystem.

Related GitHub Issues:

Shortcut Stories:
[sc-53909]

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Please edit .github/CHANGELOG.md with:

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[codecov]

Codecov Report

Attention: 5 lines in your changes are missing coverage. Please review.

Comparison is base (df43949) 98.18% compared to head (cb3f7ad) 98.38%.
Report is 1 commits behind head on master.

Files	Patch %	Lines
...ane_lightning/lightning_kokkos/lightning_kokkos.py	50.00%	4 Missing ⚠️
...ylane_lightning/lightning_qubit/lightning_qubit.py	87.50%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #591      +/-   ##
==========================================
+ Coverage   98.18%   98.38%   +0.19%     
==========================================
  Files          10      146     +136     
  Lines        1210    19324   +18114     
==========================================
+ Hits         1188    19011   +17823     
- Misses         22      313     +291     

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[mlxd]

Note: LUMI data collected using the current changes as of the latest commit.

[mlxd]

Currently pausing development until a full integration strategy has been defined.