load dotenv everywhere it's needed; postgresql pool pre ping

auth/tokens.py

@@ -2,6 +2,9 @@ from datetime import datetime, timedelta, timezone
 import os
 import jwt
 from fastapi import HTTPException, status
+from dotenv import load_dotenv
+
+load_dotenv()
 
 JWT_SECRET = os.getenv("JWT_SECRET")
 JWT_ALGORITHM = os.getenv("JWT_ALGORITHM", "HS256")