- Add cpdef wrappers (get_placed_squares, get_placed_corners) for Python
accessibility of previously cdef-only methods
- Add get_standard_pieces() to expose Cython standard piece set
- Add is_game_over(), get_scores(), get_winners() to Cython BlokusGame
- Fix valid_move() player_occupied lookup (was using player_idx instead
of player_idx+1, causing bots to fail after first move)
- Update session.py, app.py, bots.py to use Cython with pure Python fallback
- Fix board.grid.tolist() to np.array(grid).tolist() for memoryview compat
- Add Cython build artifacts to .gitignore
mattlamb227@gmail.com