Splatter: ball economy — one ball, fetch it back, no more toss-spam

The slingshot serve didn't fix the gameplay because four things were free at
once: pure-hold auto-target with predictive lead, a hardcoded 0.62 serve
quality, infinite ammo with an instant mid-rally re-toss, and a melee swish on
every single tap that cleaved the whole cluster. Perfecting the pretoss/toss
rhythm beat the game; no skill required.

The ball is scarce now. A spent ball LIES where it died (G.loose, ringed on
court) and there is no serve until it's back in your hand: walk it down
(instant, and the only reason to leave the baseline), let a boy scoop it, wait
out TUNE.looseMax, or watch a shambler swallow it — the one real punishment.
Fire rate is a positioning decision instead of a thumb-tempo one.

Also: the far backstop rebounds a ball with pace left, still lethal on the way
home and volleyable (trySwing lets P re-hit their own ball in splatter); melee
drops to nearest-one-only on a 1s cooldown; and the mid-rally re-toss is gone.
With no ball in hand the thumb-drag steers your legs instead of the reticle —
without that, walking your ball down is impossible on touch.

TUNE.looseMax is the fire-rate knob. Measured: ~4s per serve standing still,
~0.4s if you go and get it. 600 taps in 10s now yield exactly one serve.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

config.js

@@ -31,6 +31,15 @@ export const TUNE = {
   zSplatQ: 0.5,     // min shot quality to splatter; below = stagger pushback
   zPushback: 1.4,   // m a staggered zombie is knocked back
   splatterOverT: 0.1, // s the spent-ball 'over' beat lasts before the next serve is armed
+  // ball economy: a dead ball LIES on the court. No serve until it's back in your hand.
+  pickupR: 1.4,     // m — walk over your loose ball to pick it up instantly (the fast way)
+  eatBallR: 0.8,    // m — a shambler this close to a loose ball swallows it
+  looseMax: 2.0,    // s before the boys hand you one anyway — the ceiling on standing ball-less. THE fire-rate knob.
+  fetchEaten: 3.5,  // s until fresh balls arrive after one got eaten — the only real punishment in the economy
+  backstopZ: -1.8,  // z of the far backstop — must sit IN FRONT of the -2 retire line, or balls die before they reach it
+  backstopKeep: 0.55, // pace a ball keeps after the rebound — still lethal, slower
+  backstopPop: 1.8,   // m/s of lift off the fence, so the rebound travels back instead of dying at the net posts
+  meleeCool: 1.0,   // s between racket swishes — melee is the panic button, not the default
   zPierce: 0.75,    // pace a ball keeps after a splatter — hot balls plow through lined-up pairs
   ballChangeFirst: 3, // game of the first new-balls delivery (real rule: 7, then every 9 — too sparse here)
   ballChangeEvery: 4, // games between deliveries after the first