feat: 诊断（任务书 18 第一块）：诊断数学、四种提交、一次运行跑多个实验、账本与材料、flow 诊断各步

消融默认关，关掉时解释阶段一并跳过；选诊断实验用信息价值减成本。
eval/diagnosis/research.json 为第三块配置。vocab 字段说明的出口文字随提示词一起改，见下一次提交的 prompts/ 与同文件改动（本次含在内）。

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

tests/config-check.test.ts

@@ -177,6 +177,7 @@ test("写不出来的组合：朴素循环里写开关、规则或它用不到
     critique: false,
     firstPrediction: false,
     roundZero: { enabled: false },
+    diagnosis: { enabled: false },
     ablation: { enabled: false },
     batchRule: "uniformRandom",
     openReserve: 0.1,
@@ -200,6 +201,35 @@ test("写不出来的组合：关掉的第零轮写讨论次数、关掉的消
   assert.match(errorOf(ablation), /^\/flow\/ablation\/cellRule：不认识的字段$/m);
 });
 
+/** 诊断开着的完整流程配置。 */
+function diagnosisConfig(): ReturnType<typeof fullConfig> {
+  const config = fullConfig();
+  (config.flow as Obj).diagnosis = { enabled: true, perResearcher: 2, maxExperiments: 4 };
+  return config;
+}
+
+test("诊断：开着的配置通过校验；逐个删字段、写 0、写小数、多写字段都报错；关着的不能写两个参数", () => {
+  assert.deepEqual(checkConfig(structuredClone(diagnosisConfig())), diagnosisConfig());
+
+  for (const key of ["enabled", "perResearcher", "maxExperiments"]) {
+    const config = diagnosisConfig();
+    delete ((config.flow as Obj).diagnosis as Obj)[key];
+    assert.match(errorOf(config), new RegExp(`^/flow/diagnosis/${key}：`, "m"));
+  }
+  const cases: Array<[Obj, RegExp]> = [
+    [{ enabled: true, perResearcher: 0, maxExperiments: 4 }, /^\/flow\/diagnosis\/perResearcher：不能小于 1$/m],
+    [{ enabled: true, perResearcher: 2, maxExperiments: 2.5 }, /^\/flow\/diagnosis\/maxExperiments：应为整数$/m],
+    [{ enabled: true, perResearcher: 2, maxExperiments: 4, rule: "x" }, /^\/flow\/diagnosis\/rule：不认识的字段$/m],
+    [{ enabled: false, perResearcher: 2 }, /^\/flow\/diagnosis\/perResearcher：不认识的字段$/m],
+    [{ enabled: "yes" }, /^\/flow\/diagnosis\/enabled：缺少或取值不对，只能是 false、true 之一$/m],
+  ];
+  for (const [diagnosis, expected] of cases) {
+    const config = fullConfig();
+    (config.flow as Obj).diagnosis = diagnosis;
+    assert.match(errorOf(config), expected);
+  }
+});
+
 test("写不出来的组合：规则名不在 rules 登记表里", () => {
   const batch = fullConfig();
   (batch.flow as Obj).batchRule = "expected-best";