Fix config path, env secrets, and align API calls

backend/auth/login.py

@@ -13,6 +13,10 @@ def login_route():
     username = data.get('username')
     password = data.get('password')
 
+    if not SECRET_KEY:
+        logger.error("Login blocked: SECRET_KEY is not configured.")
+        return jsonify({"message": "Server misconfigured"}), 500
+
     try:
         config = load_config()
         conn = connect(**config)