Zombie mode: kills-per-point knob so a game isn't 4 pot-shots

1 kill = 1 point made a tennis game trivially short (4 kills). Gate
player scoring behind TUNE.killsPerPoint (default 3) — K kills bank one
point, the rest just splatter. Opponent breaches stay 1-for-1, so the
asymmetry is where the pressure comes from. Live-tunable in the T panel;
set to 1 to restore the old behavior.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

gameplay.js

@@ -221,6 +221,8 @@ function pointTo(side, reason) {
 // The scoreboard IS the progression: games drive spawn pressure, 6 games = a set = a horde,
 // odd games end in a changeover breather.
 export function splatPoint(side, quiet = false) {
+  if (side === 'P' && ++G.killCount < TUNE.killsPerPoint) return; // K kills bank one point; the rest just splatter
+  if (side === 'P') G.killCount = 0;
   const gameOver = advancePoint(side);
   if (gameOver) {
     G.runGames++;