[ENH] Consistent extension sampling of CPDAG, PDAG and DAG

[adam2392]

Fixes #38

Changes proposed in this pull request:

• Addresses going from DAG to CPDAG and CPDAG to DAG

This implements the relevant algorithms needed to go to/from DAG, PDAG and CPDAG. These are all useful for representing classes of graphs encoding similar, or the same relevant d-separation invariances. These suite of functions are ultimately useful for implementing "Greedy Equivalent Search (GES)" natively in dodiscover.

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[adam2392]

@aryan26roy no rush, but whenever you have the chance, perhaps you'd be interested in reviewing this PR.

cc: @jaron-lee too

[codecov]

Codecov Report

Attention: 2 lines in your changes are missing coverage. Please review.

Comparison is base (9c6a556) 77.39% compared to head (4a1cd8f) 78.04%.

❗ Current head 4a1cd8f differs from pull request most recent head 8cba951. Consider uploading reports for the commit 8cba951 to get more accurate results

Files	Patch %	Lines
pywhy_graphs/algorithms/generic.py	81.81%	1 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #102      +/-   ##
==========================================
+ Coverage   77.39%   78.04%   +0.65%     
==========================================
  Files          43       44       +1     
  Lines        3614     3731     +117     
  Branches     1053     1089      +36     
==========================================
+ Hits         2797     2912     +115     
- Misses        596      597       +1     
- Partials      221      222       +1     

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[aryan26roy]

@aryan26roy no rush, but whenever you have the chance, perhaps you'd be interested in reviewing this PR.

cc: @jaron-lee too

@adam2392 Sorry for the late reply. Will review!

[jaron-lee]

I did a lightweight review - mostly looks good to me but I'm a bit out of the loop so could have missed some bigger picture thingsg.

[adam2392]

Thanks for the reviews @jaron-lee and @aryan26roy !