refactor(frontend): clarify toVM/PROCEED 提取到 clarify.ts 共享（WFW-9 M2）

apps/web/lib/workbench/clarify.test.ts

@@ -1,8 +1,10 @@
 import { describe, expect, it } from "vitest";
 
 import {
+  PROCEED,
   foldClarifications,
   needsClarifyGate,
+  toVM,
   type ClarifyAnswer,
 } from "./clarify";
 
@@ -67,6 +69,70 @@ describe("foldClarifications", () => {
   });
 });
 
+describe("toVM", () => {
+  it("snake_case ClarifyDecision → camelCase VM，逐字段映射", () => {
+    const vm = toVM({
+      need_clarification: true,
+      questions: [
+        {
+          question: "想更冷峻还是更抒情？",
+          options: [
+            { label: "冷峻", value: "改得更冷峻克制" },
+            { label: "抒情", value: "改得更抒情" },
+          ],
+          allow_free_text: true,
+        },
+      ],
+      verification: "我这样理解对吗",
+    });
+
+    expect(vm).toEqual({
+      needClarification: true,
+      questions: [
+        {
+          question: "想更冷峻还是更抒情？",
+          options: [
+            { label: "冷峻", value: "改得更冷峻克制" },
+            { label: "抒情", value: "改得更抒情" },
+          ],
+          allowFreeText: true,
+        },
+      ],
+      verification: "我这样理解对吗",
+    });
+  });
+
+  it("字段缺省时取安全默认（空/false/undefined），不信任外部数据", () => {
+    const vm = toVM({});
+    expect(vm).toEqual({
+      needClarification: false,
+      questions: [],
+      verification: undefined,
+    });
+  });
+
+  it("questions/options 内字段缺省时逐项补默认", () => {
+    const vm = toVM({
+      need_clarification: true,
+      questions: [{ question: undefined, options: [{}], allow_free_text: undefined }],
+      verification: null,
+    });
+    expect(vm).toEqual({
+      needClarification: true,
+      questions: [
+        { question: "", options: [{ label: "", value: "" }], allowFreeText: false },
+      ],
+      verification: undefined,
+    });
+  });
+});
+
+describe("PROCEED", () => {
+  it("放行常量：不反问、无问题", () => {
+    expect(PROCEED).toEqual({ needClarification: false, questions: [] });
+  });
+});
+
 describe("needsClarifyGate", () => {
   it("去空白后长度小于 minChars 时需要预检", () => {
     expect(needsClarifyGate("改一下", 8)).toBe(true);