Fix pydantic error by adding ClassVar type annotation to DB_DIR

generated with BackendIM... (backend.im)

app/core/config.py

@@ -1,4 +1,4 @@
-from typing import List, Optional, Union
+from typing import List, Optional, Union, ClassVar
 from pathlib import Path
 from pydantic import AnyHttpUrl, validator
 from pydantic_settings import BaseSettings
@@ -6,7 +6,7 @@ from pydantic_settings import BaseSettings
 class Settings(BaseSettings):
     API_V1_STR: str = "/api/v1"
     PROJECT_NAME: str = "Quick REST API Service"
-    
+
     # CORS settings
     BACKEND_CORS_ORIGINS: List[AnyHttpUrl] = []
 
@@ -19,7 +19,7 @@ class Settings(BaseSettings):
         raise ValueError(v)
 
     # Database settings
-    DB_DIR = Path("/app/storage/db")
+    DB_DIR: ClassVar[Path] = Path("/app/storage/db")
     DB_DIR.mkdir(parents=True, exist_ok=True)
     SQLALCHEMY_DATABASE_URL: str = f"sqlite:///{DB_DIR}/db.sqlite"