feedback5 R4: one file per operator kit — kits/tier1..6.js split into kits/ops/<chessId>-<codename>.js (129 kits), kits/shared/tier1..6.js (the helpers two or more kits of a tier use, and each tier's header notes) and kits/index.js (the registry, same keys in the same order); the tier files become re-export shims

Pure move: every line of a kit, of a helper and of the tier headers is copied verbatim (only the headers' first
line names the new file); a helper used by one kit moved into that kit's file. Glue only: the generated imports,
`export default { … }` around each registry entry, `export { … }` lists in shared/tier2..6.js, and tier4's
`(bb, chess, def)` default-argument wrapper as shared/tier4.js `withDefaults` (applied in each tier-4 kit file).
kits/index.js loads every kit file with a guarded dynamic import (browser-safe, no directory listing); tierN.js
re-export the tier registry (TIER_KITS) and their old named exports (tier1 helpers + tinmanKit, tier6
PITHST_ELEMENTS). The merged registry, every tier default and named export have the same keys, order, frozenness
and function sources as before. test/docs-consistency.test.js reads the moved code at its new paths.
Golden: GOLDEN_FULL=1 node --test test/golden.test.js unchanged.

server/sim/content/kits/ops/chess_char_4_06-kroos2.js

@@ -0,0 +1,50 @@
+// server/sim/content/kits/ops/chess_char_4_06-kroos2.js — 寒芒克洛丝 (char_1021_kroos2) kit, tier 4.
+// Conventions of the tier-4 kits: ../shared/tier4.js; kit contract and rules: ../README.md.
+
+import { num, tbb, batFlat, skillActive, isSel, alt, withDefaults } from '../shared/tier4.js';
+
+export default withDefaults({
+  // ===== 寒芒克洛丝 (fastshot) S2 封喉 — double shot → 4 shots after 40 hits; talent 中的 (20 % ×1.5 + 0.2 s stun)
+  //       S1 无痕 (ATK up, double shot, 迷彩 = the engine's `camou` flag: only an enemy she blocks targets her)
+  chess_char_4_06_a: (bb, chess, def) => {
+    const t0 = tbb(def, 0);
+    const need = num(bb['attack@max_stack_count'], 40);
+    const S2 = isSel(def, 'skchr_kroos2_2');
+    return {
+      skills: alt(def, {
+        skchr_kroos2_1: () => ({
+          kind: 'duration',
+          mods: { atkPct: num(bb.atk) },
+          flags: { camou: true },
+          attack: { hits: 2 },
+          onStart({ battle, unit }) { battle.fx('camouflage', { x: unit.x, y: unit.y, id: unit.id }); },
+        }),
+      }),
+      skill: {
+        kind: 'duration',
+        mods: { batPct: batFlat(def, bb.base_attack_time) },
+        attack: { hitsFn: (battle, unit) => ((unit.mem.kroosHits ?? 0) >= need ? 4 : 2) },
+        onStart({ unit }) { unit.mem.kroosHits = 0; },
+      },
+      talents: [{ install(battle, unit) {
+        // 中的: the ×1.5 is rolled before mitigation; the stun (and the S2 "击中目标" count) only for shots that landed
+        const crits = new WeakSet();
+        battle.on('hit', (c) => {
+          if (c.source !== unit || !c.dmg.isAttack || c.target.side !== 'enemy') return;
+          if (battle.rng.chance(num(t0.prob, 0.2))) { c.dmg.mul *= num(t0.atk_scale, 1.5); crits.add(c.dmg); }
+        }, { owner: unit });
+        battle.on('damaged', (c) => {
+          if (c.source !== unit || !c.dmg || !c.dmg.isAttack || c.target.side !== 'enemy') return;
+          if (S2 && skillActive(unit)) {
+            unit.mem.kroosHits = (unit.mem.kroosHits ?? 0) + 1;
+            if (unit.mem.kroosHits === need) battle.fx('quadShot', { x: unit.x, y: unit.y, id: unit.id });
+          }
+          if (!crits.has(c.dmg)) return;
+          crits.delete(c.dmg);
+          if (c.target.alive) battle.applyStatus(c.target, 'stun', { duration: num(t0.stun, 0.2), source: unit });
+          battle.fx('crit', { x: c.target.x, y: c.target.y, id: c.target.id });
+        }, { owner: unit });
+      } }],
+    };
+  },
+});