add FEN history to the game state

fix: wrong error code when king moves into check and missing auto-disambiguation when one of the candidate pieces is pinned

fix: disambiguation by row while capturing was not implemented

rename INVALID_POSITION to PIECE_NOT_FOUND

fix wrong error message when move indices are invalid

fix incorrect move notation when disambiguating moves

fix that en passant captures do not work

(0) -100 -30 -10 -7 tip

mercurial