GUI: Handle authentication failure

src/aare/gui/auth.py

@@ -28,11 +28,13 @@ def auth(base_url: str | None) -> str:
                 "Content-Type": "application/x-www-form-urlencoded"
             }
         )
-
         if response.status_code == 200:
             response_json = response.json()
             if "access_token" in response_json:
                 return response_json["access_token"]
+        else:
+            logger.error(f"Authentication request failed: {response.content}")
+            raise Exception("Authentication request failed")
 
     except requests.RequestException as e:
         logger.error(f"Authentication request failed: {e}")