feat(python/fmt/cif): add utility function to convert DDL2 CIF to dict

[jnooree]

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 91.18%. Comparing base (41b0a4d) to head (29ae430).
Report is 4 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #446      +/-   ##
==========================================
+ Coverage   91.15%   91.18%   +0.02%     
==========================================
  Files          58       58              
  Lines       13434    13477      +43     
==========================================
+ Hits        12246    12289      +43     
  Misses       1188     1188              

Files with missing lines	Coverage Δ
python/src/nuri/fmt/cif.cpp	94.52% <100.00%> (+2.13%)	⬆️

... and 1 file with indirect coverage changes