refactor: 更新主应用和依赖

- 在主应用中注册认证路由
- 更新requirements.txt添加认证相关依赖（jose, passlib, bcrypt）

api/main.py

@@ -11,7 +11,7 @@ from fastapi.middleware.cors import CORSMiddleware
 load_dotenv()
 
 from database import init_db
-from routers import websocket, chapters, books, conversations
+from routers import websocket, chapters, books, conversations, auth
 
 # 初始化数据库
 init_db()
@@ -28,6 +28,7 @@ app.add_middleware(
 )
 
 # 注册路由
+app.include_router(auth.router)  # 认证路由（放在最前面）
 app.websocket("/ws/conversation/{conversation_id}")(websocket.websocket_endpoint)
 app.include_router(conversations.router)
 app.include_router(chapters.router)