Add checkmask and pinmask

[Jan-Frase]

https://www.chessprogramming.org/Attack_and_Defend_Maps

Should be done after proper benchmarking is in place.

[Jan-Frase]

Idea from here:
https://web.archive.org/web/20250910134338/https://www.codeproject.com/articles/Worlds-fastest-Bitboard-Chess-Movegenerator