Use standard depth concept in NegaMax method

[eduherminio]

Replace custom-made fixed targetDepth and increasing ply schema, where ply == targetDepth was used to trigger QSearch, with the standard, decreasing depth by one + reductions, and increasing ply by one no-matter-what.

0349afb ([-5, 0] 8+0.08 vs main, -draw and -resign) 👍🏽
And no illegal PV move warnings 😊
But might need to revisit stalemates detection

Score of Lynx 1348 - refactor depth vs Lynx 1345 - main: 6122 - 6074 - 3440  [0.502] 15636
...      Lynx 1348 - refactor depth playing White: 3742 - 2412 - 1663  [0.585] 7817
...      Lynx 1348 - refactor depth playing Black: 2380 - 3662 - 1777  [0.418] 7819
...      White vs Black: 7404 - 4792 - 3440  [0.584] 15636
Elo difference: 1.1 +/- 4.8, LOS: 66.8 %, DrawRatio: 22.0 %
SPRT: llr 2.96 (100.6%), lbound -2.94, ubound 2.94 - H1 was accepted

Player: Lynx 1348 - refactor depth
   "Draw by 3-fold repetition": 1679
   "Draw by adjudication": 686
   "Draw by fifty moves rule": 210
   "Draw by insufficient mating material": 834
   "Draw by stalemate": 31
   "Loss: Black mates": 22
   "Loss: Black wins by adjudication": 2389
   "Loss: White loses on time": 1
   "Loss: White mates": 37
   "Loss: White wins by adjudication": 3625
   "No result": 7
   "Win: Black loses on time": 3
   "Win: Black mates": 21
   "Win: Black wins by adjudication": 2355
   "Win: White loses on time": 4
   "Win: White mates": 36
   "Win: White wins by adjudication": 3703
Player: Lynx 1345 - main
   "Draw by 3-fold repetition": 1679
   "Draw by adjudication": 686
   "Draw by fifty moves rule": 210
   "Draw by insufficient mating material": 834
   "Draw by stalemate": 31
   "Loss: Black loses on time": 3
   "Loss: Black mates": 21
   "Loss: Black wins by adjudication": 2355
   "Loss: White loses on time": 4
   "Loss: White mates": 36
   "Loss: White wins by adjudication": 3703
   "No result": 7
   "Win: Black mates": 22
   "Win: Black wins by adjudication": 2389
   "Win: White loses on time": 1
   "Win: White mates": 37
   "Win: White wins by adjudication": 3625

Without -draw and -resign

Score of Lynx 1348 - depth refactor vs Lynx 1345 - main: 8619 - 8627 - 5514  [0.500] 22760
...      Lynx 1348 - depth refactor playing White: 5230 - 3381 - 2770  [0.581] 11381
...      Lynx 1348 - depth refactor playing Black: 3389 - 5246 - 2744  [0.418] 11379
...      White vs Black: 10476 - 6770 - 5514  [0.581] 22760
Elo difference: -0.1 +/- 3.9, LOS: 47.6 %, DrawRatio: 24.2 %
SPRT: llr 2.96 (100.5%), lbound -2.94, ubound 2.94 - H1 was accepted

Player: Lynx 1348 - depth refactor
   "Draw by 3-fold repetition": 3294
   "Draw by fifty moves rule": 507
   "Draw by insufficient mating material": 1652
   "Draw by stalemate": 61
   "Loss: Black mates": 3381
   "Loss: White mates": 5246
   "No result": 7
   "Win: Black makes an illegal move: a8a8": 1
   "Win: Black mates": 3389
   "Win: White mates": 5229
Player: Lynx 1345 - main
   "Draw by 3-fold repetition": 3294
   "Draw by fifty moves rule": 507
   "Draw by insufficient mating material": 1652
   "Draw by stalemate": 61
   "Loss: Black makes an illegal move: a8a8": 1
   "Loss: Black mates": 3389
   "Loss: White mates": 5229
   "No result": 7
   "Win: Black mates": 3381

71397c4 ([0, 5] 8+0.08 vs main, -draw and -resign) 👍🏽
And no illegal PV move warnings either

Score of Lynx 1349 - refactor depth vs Lynx 1345 - main: 2780 - 2573 - 1645  [0.515] 6998
...      Lynx 1349 - refactor depth playing White: 1698 - 994 - 808  [0.601] 3500
...      Lynx 1349 - refactor depth playing Black: 1082 - 1579 - 837  [0.429] 3498
...      White vs Black: 3277 - 2076 - 1645  [0.586] 6998
Elo difference: 10.3 +/- 7.1, LOS: 99.8 %, DrawRatio: 23.5 %
SPRT: llr 2.95 (100.1%), lbound -2.94, ubound 2.94 - H1 was accepted

Without -draw and -resign: 👍🏽

Score of Lynx 1349 - refactor depth vs Lynx 1345 - main: 1258 - 1082 - 795  [0.528] 3135
...      Lynx 1349 - refactor depth playing White: 742 - 433 - 394  [0.598] 1569
...      Lynx 1349 - refactor depth playing Black: 516 - 649 - 401  [0.458] 1566
...      White vs Black: 1391 - 949 - 795  [0.570] 3135
Elo difference: 19.5 +/- 10.5, LOS: 100.0 %, DrawRatio: 25.4 %
SPRT: llr 2.96 (100.6%), lbound -2.94, ubound 2.94 - H1 was accepted

Player: Lynx 1349 - refactor depth
   "Draw by 3-fold repetition": 472
   "Draw by fifty moves rule": 75
   "Draw by insufficient mating material": 240
   "Draw by stalemate": 8
   "Loss: Black mates": 433
   "Loss: White mates": 649
   "No result": 7
   "Win: Black mates": 516
   "Win: White mates": 742
Player: Lynx 1345 - main
   "Draw by 3-fold repetition": 472
   "Draw by fifty moves rule": 75
   "Draw by insufficient mating material": 240
   "Draw by stalemate": 8
   "Loss: Black mates": 516
   "Loss: White mates": 742
   "No result": 7
   "Win: Black mates": 433
   "Win: White mates": 649

Unfinished run, it was also looking good

Score of Lynx 1349 - depth refactor vs Lynx 1345 - main: 1188 - 1121 - 725  [0.511] 3034
...      Lynx 1349 - depth refactor playing White: 700 - 448 - 369  [0.583] 1517
...      Lynx 1349 - depth refactor playing Black: 488 - 673 - 356  [0.439] 1517
...      White vs Black: 1373 - 936 - 725  [0.572] 3034
Elo difference: 7.7 +/- 10.8, LOS: 91.8 %, DrawRatio: 23.9 %
SPRT: llr 0.854 (29.0%), lbound -2.94, ubound 2.94

Player: Lynx 1349 - depth refactor
   "Draw by 3-fold repetition": 361
   "Draw by adjudication": 133
   "Draw by fifty moves rule": 42
   "Draw by insufficient mating material": 183
   "Draw by stalemate": 6
   "Loss: Black loses on time": 1
   "Loss: Black mates": 4
   "Loss: Black wins by adjudication": 444
   "Loss: White mates": 2
   "Loss: White wins by adjudication": 670
   "No result": 4
   "Win: Black mates": 3
   "Win: Black wins by adjudication": 485
   "Win: White mates": 4
   "Win: White wins by adjudication": 696
Player: Lynx 1345 - main
   "Draw by 3-fold repetition": 361
   "Draw by adjudication": 133
   "Draw by fifty moves rule": 42
   "Draw by insufficient mating material": 183
   "Draw by stalemate": 6
   "Loss: Black mates": 3
   "Loss: Black wins by adjudication": 485
   "Loss: White mates": 4
   "Loss: White wins by adjudication": 696
   "No result": 4
   "Win: Black loses on time": 1
   "Win: Black mates": 4
   "Win: Black wins by adjudication": 444
   "Win: White mates": 2
   "Win: White wins by adjudication": 670

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