Two frames each: the run cycles land where the zombies always were

The live bench session's verdict, in Oliver's words: "this looks better than
anything before." Six and eight real phases at speed read as flicker on a
far-court body — the zombies never had this problem because their walks are
FOUR well-chosen frames at a calm rate, and the fix was to stop out-drawing
them. Each opponent now runs a TWO-frame true leg-swap pair — his frames 1+2
of the grid roll, hers 7+8 of the face-transplant cycle, both picked live on
the bench with SPR swaps — at TUNE.runHz2 = 1.7 (the old hardcoded 4.5 for
short cycles was most of a stride per display frame; that is the strobe).

The tuning rig ships too: TUNE.runN (frame-count override, 0 = probe),
T.SPR for live frame swaps, and the bench's living slots — the next cadence
question gets answered by watching, not rolling. Twelve run sprites become
four; the SPR list says why. SPRV 124, main.js v248.

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

src/main.js

@@ -7,7 +7,7 @@ import { TUNE, COURTS, TOURS, MODES, MENU, DIFFS, EATEN_RESTART, DONE_RESTART, W
 import { P, O, ball, score, G, setupPoint, selectCourt, selectTour } from './state.js';
 import { update, restartRun, keyPressed, solveShot, inServeBox, inCourt, forceZombies, splatPoint, deliverTin, selectWeapon, grantWeapon, showModal, dismissModal, flickTarget, dragServe, toggleTestMode } from './gameplay.js';
 import { startDuel, resolveInterlude, startBossFight, endBossFight, startDrill, endDrill, startMatch, endMatch, startBench, endBench, FALL, benchFall } from './beats.js';
-import { fitViewport, render, proj, RES, SPRV, LOAD } from './render.js';
+import { fitViewport, render, proj, RES, SPRV, LOAD, SPR } from './render.js';
 import { voice, ambient, menuMusic, menuDuck } from './audio.js';
 import { zombies, spawnZombie, spawnRacketZombie, spawnMachine, spawnChapterBoss, piles, gore, parts, pellets, extras, shots, pops, explode, hurtPlayer, killPlayer , spawnBarrel } from './zombies.js';
 import { cv } from './dom.js';
@@ -556,6 +556,6 @@ if (location.hash === '#bench') setTimeout(() => { start(null); intoSplatter();
 requestAnimationFrame(frame);
 
 // exposed for in-browser sanity checks and simulated playtests
-window.T = { TUNE, ball, P, O, score, G, zombies, keyPressed, laserScene, laserFire, pause: v => { paused = v !== false; }, spawnZombie, spawnRacketZombie, spawnMachine, spawnChapterBoss, spawnBarrel, grantWeapon, toggleTestMode, piles, gore, parts, pellets, extras, shots, pops, explode, hurtPlayer, killPlayer, splatPoint, solveShot, inServeBox, inCourt, proj, setupPoint, forceZombies, deliverTin, selectWeapon, showModal, dismissModal, dragServe, startDuel, resolveInterlude, flickTarget, startBossFight, endBossFight, startDrill, endDrill, startMatch, endMatch,
+window.T = { TUNE, ball, P, O, score, G, zombies, keyPressed, SPR, laserScene, laserFire, pause: v => { paused = v !== false; }, spawnZombie, spawnRacketZombie, spawnMachine, spawnChapterBoss, spawnBarrel, grantWeapon, toggleTestMode, piles, gore, parts, pellets, extras, shots, pops, explode, hurtPlayer, killPlayer, splatPoint, solveShot, inServeBox, inCourt, proj, setupPoint, forceZombies, deliverTin, selectWeapon, showModal, dismissModal, dragServe, startDuel, resolveInterlude, flickTarget, startBossFight, endBossFight, startDrill, endDrill, startMatch, endMatch,
   stats, step: dt => update(dt), render, press: keyPressed, FALL, benchFall,
   get phase() { return G.phase; }, set phase(v) { G.phase = v; } };