引入二级大纲功能，新增父子节点关系及子节点排序，同时调整API与UI以支持嵌套大纲管理

backend/app/main.py

@@ -1,7 +1,10 @@
 from contextlib import asynccontextmanager
+from pathlib import Path
 
 from fastapi import FastAPI
 from fastapi.middleware.cors import CORSMiddleware
+from fastapi.staticfiles import StaticFiles
+from starlette.responses import FileResponse
 
 from .database import init_db
 from .routers.novels import router as novels_router
@@ -12,6 +15,9 @@ from .routers.world_setting import router as world_setting_router
 from .routers.ai_config import router as ai_config_router
 from .routers.chat import router as chat_router
 
+# 前端构建产物目录（Docker 中为 /app/static，本地开发时不存在则跳过）
+STATIC_DIR = Path(__file__).resolve().parent.parent / "static"
+
 
 @asynccontextmanager
 async def lifespan(app: FastAPI):
@@ -23,7 +29,7 @@ app = FastAPI(title="Noval", version="0.1.0", lifespan=lifespan)
 
 app.add_middleware(
     CORSMiddleware,
-    allow_origins=["http://localhost:5173"],
+    allow_origins=["*"],
     allow_credentials=True,
     allow_methods=["*"],
     allow_headers=["*"],
@@ -41,3 +47,17 @@ app.include_router(chat_router)
 @app.get("/api/health")
 def health():
     return {"status": "ok"}
+
+
+# 生产环境：serve 前端静态文件（Vue SPA）
+if STATIC_DIR.is_dir():
+    # 静态资源（js/css/img）
+    app.mount("/assets", StaticFiles(directory=STATIC_DIR / "assets"), name="assets")
+
+    # 所有非 /api 路径返回 index.html（Vue Router history 模式）
+    @app.get("/{path:path}")
+    async def spa_fallback(path: str):
+        file_path = STATIC_DIR / path
+        if file_path.is_file():
+            return FileResponse(file_path)
+        return FileResponse(STATIC_DIR / "index.html")