Introduce 4-ply continuation correction history
Passed STC:
LLR: 2.94 (-2.94,2.94) <0.00,2.00>
Total: 113984 W: 29752 L: 29323 D: 54909
Ptnml(0-2): 376, 13191, 29435, 13608, 382
https://tests.stockfishchess.org/tests/view/68dc3576fa806e2e8393bd93
Passed LTC:
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 80154 W: 20823 L: 20417 D: 38914
Ptnml(0-2): 47, 8600, 22383, 8994, 53
https://tests.stockfishchess.org/tests/view/68df83e0fa806e2e8393cbe8
Passed non-regression VLTC (rebased):
LLR: 2.98 (-2.94,2.94) <-1.75,0.25>
Total: 38158 W: 9992 L: 9805 D: 18361
Ptnml(0-2): 3, 3406, 12075, 3591, 4
https://tests.stockfishchess.org/tests/view/68e22f2afa806e2e8393d0ed
closes https://github.com/official-stockfish/Stockfish/pull/6345
bench 2169281