feat(web): 立项新增 基调/结局/视角 三字段（书级常量入 stable_core 缓存前缀）

灵感计划 §3④ + §4 D 枚举决策：
- projects 表加 tone/ending_type/narrative_pov（Text nullable、无 CHECK，同 genre/structure；
  迁移 e5f6a7b8c9d0 nullable 免 backfill）。
- ProjectCreateRequest/ProjectResponse + domain ProjectCreate/ProjectView 全链路透传（snake_case）。
- 完整 stable_core 链路：ProjectSpecView + SqlProjectSpecRepo.spec + _build_spec_section 渲染进
  「作品蓝本」块——书级常量随书稳定，字节稳定守缓存前缀不变量 #9，绝不入 volatile。
- 前端 wizard.ts 三字段 + 预设数组 TONES/ENDING_TYPES/NARRATIVE_POVS + ProjectWizard 控件与确认页回显。
- 契约变更已 pnpm gen:api + memory/contracts.md 登记。

apps/api/tests/fakes_projects.py

@@ -55,6 +55,9 @@ class FakeProjectRepo:
             theme=data.theme,
             selling_points=list(data.selling_points),
             structure=data.structure,
+            tone=data.tone,
+            ending_type=data.ending_type,
+            narrative_pov=data.narrative_pov,
             updated_at=self.now,
         )
         self.rows[pid] = (owner_id, view)

apps/api/tests/test_projects.py

@@ -150,6 +150,54 @@ async def test_create_project_returns_201() -> None:
     assert uuid.UUID(body["id"])
 
 
+@pytest.mark.asyncio
+async def test_create_project_persists_tone_ending_pov() -> None:
+    # ④ 立项新增基调/结局/视角：请求 → repo 落库 → 响应回显（snake_case 契约）。
+    client, repo, _, _ = _make_client()
+    async with client:
+        resp = await client.post(
+            "/projects",
+            json={
+                "title": "基调作品",
+                "tone": "热血",
+                "ending_type": "HE",
+                "narrative_pov": "第一人称",
+            },
+        )
+    assert resp.status_code == 201
+    body = resp.json()
+    assert body["tone"] == "热血"
+    assert body["ending_type"] == "HE"
+    assert body["narrative_pov"] == "第一人称"
+    (_owner, view) = next(iter(repo.rows.values()))
+    assert view.tone == "热血"
+    assert view.ending_type == "HE"
+    assert view.narrative_pov == "第一人称"
+
+
+@pytest.mark.asyncio
+async def test_get_project_exposes_tone_ending_pov() -> None:
+    client, _, _, _ = _make_client()
+    async with client:
+        created = (
+            await client.post(
+                "/projects",
+                json={
+                    "title": "书",
+                    "tone": "沉重",
+                    "ending_type": "BE",
+                    "narrative_pov": "多视角",
+                },
+            )
+        ).json()
+        resp = await client.get(f"/projects/{created['id']}")
+    assert resp.status_code == 200
+    body = resp.json()
+    assert body["tone"] == "沉重"
+    assert body["ending_type"] == "BE"
+    assert body["narrative_pov"] == "多视角"
+
+
 @pytest.mark.asyncio
 async def test_list_projects() -> None:
     client, repo, _, _ = _make_client()