[Chess] Add game class

[sotetsuk]

#1127

[codecov]

Codecov Report

Attention: Patch coverage is 95.08197% with 3 lines in your changes missing coverage. Please review.

Project coverage is 80.63%. Comparing base (6a938ef) to head (fc54841).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
pgx/_src/games/chess.py	94.64%	3 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1229      +/-   ##
==========================================
- Coverage   80.65%   80.63%   -0.03%     
==========================================
  Files          62       62              
  Lines        5956     5963       +7     
==========================================
+ Hits         4804     4808       +4     
- Misses       1152     1155       +3     

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