Difficulty moves the dials a player can feel: reaction, reach, floor, serve

"using the difficulty in classic tennis I don't feel any difference" — and he
was right, verified live: G.diff arrives intact, the dials were just the
wrong ones. flub/cap/speed barely register: the quality cap trims a
distribution whose 0.45 floor never moved (EASY and HARD averaged 0.59 vs
0.70), and ±12% on aiSpeed never binds because the CPU pre-plans its
intercept. What a player reads as SKILL is how fast the CPU reacts to the
shot (aiReaction — the config's own comment says corners are winners because
of it), how long its racket is (aiReach), the FLOOR of its shot quality (a
raised qMin means every ball comes back with pace), and the serve — none of
which the first cut touched, and the serve was hardcoded 0.6-0.95 besides.

DIFFS carries seven dials now with real spread: EASY whiffs one ball in
three, reads late, swings short and serves soft; HARD reads in 0.28s, swings
1.75m, floors quality at 0.62 with a cap of 1.0, and serves 10% hotter.
MEDIUM is pinned dial-for-dial to the shipped TUNE values by test, so the
middle chip remains exactly yesterday's classic. All G.diff-guarded, so the
racket zombie and gore's opener keep their own numbers.

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

test.js

@@ -1114,15 +1114,25 @@ test('classic wears the match feel, and the difficulty table is a ladder', () =>
   assert.ok(rallyFeel(), 'classic is a rally mode');
   assert.ok(assistK() >= TUNE.matchAssist, 'classic gets the match assist floor');
   G.classic = false;
-  // ...and DIFFS climbs monotonically, with MEDIUM pinned to the shipped classic dials so the
-  // middle chip can never drift from what "no difficulty" used to play like.
+  // ...and DIFFS climbs monotonically on every dial, with MEDIUM pinned dial-for-dial to the
+  // shipped TUNE values so the middle chip can never drift from what "no difficulty" played like.
+  // (The first cut scaled only flub/cap/speed and Oliver felt no difference — reaction, reach,
+  // qMin and serve are the dials a player actually reads as skill.)
   const [e, m, h] = cfg.DIFFS;
   assert.ok(e.flub > m.flub && m.flub > h.flub, 'easier flubs more');
   assert.ok(e.quality < m.quality && m.quality < h.quality, 'harder hits better');
   assert.ok(e.speed < m.speed && m.speed < h.speed, 'harder runs faster');
+  assert.ok(e.reaction > m.reaction && m.reaction > h.reaction, 'harder reads the shot sooner');
+  assert.ok(e.reach < m.reach && m.reach < h.reach, 'harder swings a longer racket');
+  assert.ok(e.qMin <= m.qMin && m.qMin < h.qMin, 'harder raises the quality floor');
+  assert.ok(e.serve < m.serve && m.serve < h.serve, 'harder serves better');
   assert.equal(m.flub, TUNE.classicFlub, 'MEDIUM flub IS classicFlub');
   assert.equal(m.quality, TUNE.classicQualityMax, 'MEDIUM quality IS classicQualityMax');
   assert.equal(m.speed, 1.0, 'MEDIUM leaves aiSpeed alone');
+  assert.equal(m.qMin, TUNE.aiQualityMin, 'MEDIUM floor IS aiQualityMin');
+  assert.equal(m.reaction, TUNE.aiReaction, 'MEDIUM reaction IS aiReaction');
+  assert.equal(m.reach, TUNE.aiReach, 'MEDIUM reach IS aiReach');
+  assert.equal(m.serve, 1.0, 'MEDIUM leaves the serve alone');
 });
 
 // stats.js ships its own fixture-based check — the period filter, the mode split and the name