feat(toolbox): T6 创作工具箱通用生成器框架 — 8 新生成器 + 声明驱动落地页 + P2 收尾

通用执行路径驱动全部生成器（"加生成器=加一份声明"）：
- @llm: ww_agents +7 输出 schema + 7 spec（book-title/blurb/name/golden-finger/
  glossary/opening/fine-outline，只声明 tier）+ build_outline_chapter_context
- @backend: ww_skills GeneratorTool 描述符 + TOOLBOX(11) + get_tool；3 通用端点
  GET /skills/toolbox · POST .../skills/{tool_key}/generate(预览不写库,仅记账) ·
  POST .../ingest(复用 continuity 409 + partition_writes 白名单)；纯 context 派发
- @frontend: 工具箱落地页 RSC + 声明驱动 GeneratorRunner + lib/toolbox 纯函数
  + LeftNav「工具箱」+ ⌘K nav-toolbox/action-gen-*；legacy 3 跳现页
- @qa: tests/test_t6_toolbox_e2e.py 5 用例真 pg + mock 网关零 token，无端点 bug
- P2 收尾: 限流→decisions.md 记延后(单用户原型)；noopener/Committable 早已修

守不变量 #2(只声明 tier)/#3(预览不写库,入库经验收 gate)/#9(缓存前缀)。无 DB 迁移。
门禁绿: 后端 ruff/format/mypy 195/alembic 无漂移/pytest 583；前端 lint/tsc/vitest 279/build。
spec 回写 PRODUCT_SPEC §7 + ARCHITECTURE §7.2 端点表。

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

apps/api/tests/test_toolbox_context.py

@@ -0,0 +1,84 @@
+"""T6.3 创作工具箱 context 派发纯函数单测（LLM-free，确定性）。
+
+每种策略的注入文本形状 + with_outline_chapter 缺节拍降级（空 beats 不报错）。
+"""
+
+from __future__ import annotations
+
+import pytest
+from ww_api.services.toolbox_context import build_toolbox_context
+
+
+def test_brief_only_includes_setting_and_brief() -> None:
+    text = build_toolbox_context(
+        "brief_only", brief="爽文脑洞", project_context="标题：测试\n题材：玄幻"
+    )
+    assert "## 作品设定" in text
+    assert "标题：测试" in text
+    assert "## 创作需求" in text
+    assert "爽文脑洞" in text
+
+
+def test_brief_only_empty_brief_degrades() -> None:
+    text = build_toolbox_context("brief_only", brief="", project_context="标题：测试")
+    # 空 brief → 降级占位（由 system_prompt 的「自由发散」纪律处理）。
+    assert "自由发散" in text
+
+
+def test_with_project_uses_brief_context() -> None:
+    text = build_toolbox_context(
+        "with_project", brief="多版简介", project_context="标题：测试\n前提：废柴逆袭"
+    )
+    assert "前提：废柴逆袭" in text
+    assert "多版简介" in text
+
+
+def test_with_world_injects_world_block() -> None:
+    text = build_toolbox_context(
+        "with_world",
+        brief="取个名字",
+        project_context="标题：测试",
+        world_context="- [力量体系] 灵脉：灵力守恒",
+    )
+    assert "## 世界观" in text
+    assert "灵脉" in text
+    assert "取个名字" in text
+
+
+def test_with_world_empty_world_degrades() -> None:
+    text = build_toolbox_context(
+        "with_world", brief="x", project_context="标题：测试", world_context=""
+    )
+    assert "暂无世界观设定" in text
+
+
+def test_with_outline_chapter_injects_beats() -> None:
+    text = build_toolbox_context(
+        "with_outline_chapter",
+        brief="展开细纲",
+        project_context="标题：测试",
+        chapter_no=3,
+        beats=["主角觉醒", "初遇反派"],
+    )
+    assert "第 3 章大纲节拍" in text
+    assert "主角觉醒" in text
+    assert "初遇反派" in text
+    assert "展开细纲" in text
+
+
+def test_with_outline_chapter_missing_beats_does_not_error() -> None:
+    # 缺章/缺大纲 → 空节拍占位，不报错（预览降级）。
+    text = build_toolbox_context(
+        "with_outline_chapter",
+        brief="",
+        project_context="标题：测试",
+        chapter_no=99,
+        beats=[],
+    )
+    assert "第 99 章大纲节拍" in text
+    assert "暂无大纲节拍" in text
+
+
+def test_unknown_strategy_raises() -> None:
+    with pytest.raises(ValueError):
+        build_toolbox_context("nope", brief="x", project_context="y")  # type: ignore[arg-type]