fix(scope-b): 修评审 4 HIGH + 同步 T6 工具数(15)

1. T6 e2e 工具数同步：list 断言 11→15（含 continue/expand/de-ai/teardown），
   测试名 ...eleven→fifteen；保留 legacy/ingestable 意图。
2. teardown 书名（body.kind）前置入原文 → 进 text_input context（拆书 prompt 期待书名）。
3. text_input 工具（扩写/降AI/拆书）空原文 → 422 VALIDATION，不让 LLM 空跑。
4. 链 UI：busy 守卫加 awaiting，裁决期间禁止重复发起链。

测试：扩 teardown 断言书名入 context + 新增 expand 空原文 422；后端 642 passed，
前端 294 passed，两门禁全绿。

apps/api/tests/test_toolbox_endpoints.py

@@ -492,6 +492,31 @@ async def test_generate_teardown_returns_structured() -> None:
     assert body["output_kind"] == "BookTeardownResult"
     assert body["preview"]["themes"] == ["逆袭"]
     assert body["preview"]["structure"] == "黄金三章立钩"
+    # 书名（body.kind）前置入原文 → 进了喂网关的 context（拆书 prompt 期待书名）。
+    assert gateway.last_input is not None
+    assert "书名：某爆款" in gateway.last_input
+    assert "样本章节正文" in gateway.last_input
+
+
+@pytest.mark.asyncio
+async def test_generate_text_input_empty_text_422() -> None:
+    # text_input 工具（扩写/降AI/拆书）原文为空/空白 → 422，不触达网关（不让 LLM 空跑）。
+    repo = FakeProjectRepo()
+    pid = await _seed_project(repo)
+    gateway = _CaptureGateway(PolishResult(text="不应被调用。"))
+    app, session, *_ = _make_app(project_repo=repo, gateway=gateway)
+
+    async with _client(app) as client:
+        resp = await client.post(
+            f"/projects/{pid}/skills/expand/generate",
+            json={"text": "   ", "brief": "加强描写"},
+        )
+
+    assert resp.status_code == 422
+    assert resp.json()["error"]["code"] == ErrorCode.VALIDATION
+    # 校验在生成前拦下：网关未被调用、未 commit。
+    assert gateway.last_input is None
+    assert session.commits == 0
 
 
 # ---- POST .../ingest（world_entities gate）----

apps/api/ww_api/routers/toolbox.py

@@ -192,6 +192,7 @@ async def generate_with_tool(
     world_context = ""
     beats: list[str] = []
     prior_text = ""
+    text = body.text or ""
     if tool.context_strategy == "with_world":
         world_context = await _world_context(memory, project_id)
     elif tool.context_strategy == "with_outline_chapter":
@@ -202,6 +203,18 @@ async def generate_with_tool(
         chapter_no = body.chapter_no or 1
         prior_text = await _prior_chapter_text(chapter_repo, project_id, chapter_no)
         beats = await _chapter_beats(outline_repo, project_id, chapter_no)
+    elif tool.context_strategy == "text_input":
+        # text_input 工具（扩写/降AI/拆书）必须有原文样本——空原文会让 LLM 空跑（守输入校验纪律）。
+        if not text.strip():
+            raise AppError(
+                ErrorCode.VALIDATION,
+                f"工具 {tool_key} 需要原文输入（text 不可为空）",
+                {"tool_key": tool_key},
+            )
+        # 拆书的书名（body.kind）前置入原文，供拆解对照（teardown system prompt 期待书名）。
+        kind = (body.kind or "").strip()
+        if kind:
+            text = f"书名：{kind}\n\n{text}"
 
     context = build_toolbox_context(
         tool.context_strategy,
@@ -211,7 +224,7 @@ async def generate_with_tool(
         chapter_no=body.chapter_no,
         beats=beats,
         prior_text=prior_text,
-        text=body.text or "",
+        text=text,
     )
 
     gateway = await build_gateway(spec.tier)

apps/web/components/chain/ChainPage.tsx

@@ -77,7 +77,9 @@ export function ChainPage({ project }: ChainPageProps) {
 
   const showProgress = jobId !== null && result !== null;
   // 链运行中/等待裁决时禁止重复发起。
-  const busy = starting || (jobId !== null && phase === "running");
+  const busy =
+    starting ||
+    (jobId !== null && (phase === "running" || phase === "awaiting"));
 
   return (
     <AppShell