Add King Pressure evaluation

[KnightStackSys]

Adds a team-aware handcrafted King Pressure term for 4PC Teams.

Evaluation

• Scores pressure against both enemy kings at the team level.
• Combines Red+Yellow or Blue+Green before scoring, so overlapping king-zone squares are not double-counted.
• Only scores usable king-zone squares that are not occupied by the defending team.
• Requires at least two attacking pieces and at least two covered king-zone squares before awarding positional pressure.
• A zero piece weight cleanly disables that piece type from positional king pressure.
• Direct king-attack bonus is tempo-aware: it is awarded only when the attacking color is the actual side to move.
• Direct king attacks are awarded once per enemy king, since multiple checking pieces do not make a terminal king capture more valuable.
• The term is added only to the HCE path; PhoenixNet behavior is unchanged.

Current default parameters

• EvalKingPressurePawn = 0
• EvalKingPressureKnight = 3
• EvalKingPressureBishop = 3
• EvalKingPressureRook = 4
• EvalKingPressureQueen = 5
• EvalKingPressureCheckBonus = 12

All parameters remain exposed through the existing UCI tuning system, appear in tuneparams, and can be tuned by Tunex.

Revision history

• Initial version tested around -40 Elo.
• The first selectivity revision improved to roughly -16 Elo.
• This revision further reduces pseudo-pressure noise, makes direct king danger tempo-aware, disables pawn positional pressure by default, and lowers the remaining pressure weights.

This branch remains isolated for a fresh SPRT against main.

[KnightStackSys]

This is averaging around -50 elo, will do some adjustments for elo gain.