⚖ Allow bucketed PSQTs + implement friendly king related PSQTs (king/…

…queenside) (#873)

- Allow bucketed PSQTs, with a constant (`PSQTBucketCount`) that determines the number of buckets/PSQT instances per conceptual PSQT.
  They're `short[PSQTBucketCount][64]` now, with `PackedPSQT` being `short[2][12][64]` (candidate for flattenning?)
-  Make `PSQTBucketCount = 2` and split PSQTs according to friendly king in kingside or queenside of the board.

src/Lynx.Benchmark/EnumCasting_Benchmark.cs

@@ -35,12 +35,12 @@ public int Constant(int iterations)
         var sum = 0;
         for (int i = 0; i < iterations; ++i)
         {
-            sum += EvaluationConstants.MiddleGamePieceValues[Pawn];
-            sum += EvaluationConstants.MiddleGamePieceValues[Pawn];
-            sum += EvaluationConstants.MiddleGamePieceValues[Pawn];
-            sum += EvaluationConstants.MiddleGamePieceValues[Pawn];
-            sum += EvaluationConstants.MiddleGamePieceValues[Pawn];
-            sum += EvaluationConstants.MiddleGamePieceValues[Pawn];
+            sum += EvaluationConstants.MiddleGamePieceValues[0][Pawn];
+            sum += EvaluationConstants.MiddleGamePieceValues[0][Pawn];
+            sum += EvaluationConstants.MiddleGamePieceValues[0][Pawn];
+            sum += EvaluationConstants.MiddleGamePieceValues[0][Pawn];
+            sum += EvaluationConstants.MiddleGamePieceValues[0][Pawn];
+            sum += EvaluationConstants.MiddleGamePieceValues[0][Pawn];
         }
 
         return sum;
@@ -53,12 +53,12 @@ public int Cast(int iterations)
         var sum = 0;
         for (int i = 0; i < iterations; ++i)
         {
-            sum += EvaluationConstants.MiddleGamePieceValues[(int)Piece.P];
-            sum += EvaluationConstants.MiddleGamePieceValues[(int)Piece.P];
-            sum += EvaluationConstants.MiddleGamePieceValues[(int)Piece.P];
-            sum += EvaluationConstants.MiddleGamePieceValues[(int)Piece.P];
-            sum += EvaluationConstants.MiddleGamePieceValues[(int)Piece.P];
-            sum += EvaluationConstants.MiddleGamePieceValues[(int)Piece.P];
+            sum += EvaluationConstants.MiddleGamePieceValues[0][(int)Piece.P];
+            sum += EvaluationConstants.MiddleGamePieceValues[0][(int)Piece.P];
+            sum += EvaluationConstants.MiddleGamePieceValues[0][(int)Piece.P];
+            sum += EvaluationConstants.MiddleGamePieceValues[0][(int)Piece.P];
+            sum += EvaluationConstants.MiddleGamePieceValues[0][(int)Piece.P];
+            sum += EvaluationConstants.MiddleGamePieceValues[0][(int)Piece.P];
         }
 
         return sum;