update langchain integration (#2388)

integrations/langchain/skyvern_langchain/settings.py

@@ -1,13 +1,13 @@
-from typing import Literal
-
 from dotenv import load_dotenv
 from pydantic_settings import BaseSettings
 
+from skyvern.schemas.runs import RunEngine
+
 
 class Settings(BaseSettings):
     api_key: str = ""
     base_url: str = "https://api.skyvern.com"
-    engine: Literal["TaskV1", "TaskV2"] = "TaskV2"
+    engine: RunEngine = RunEngine.skyvern_v2
     run_task_timeout_seconds: int = 60 * 60
 
     class Config: