fix: show more user-friendly error message if QR code has expired

frontend/messages/en.json

@@ -562,5 +562,6 @@
 	"deny": "Deny",
 	"approve": "Approve",
 	"or": "or",
-	"visit_and_enter": "Visit {url} and enter:"
+	"visit_and_enter": "Visit {url} and enter:",
+	"device_login_request_expired": "Your QR-Code has expired. Please start the sign-in process again."
 }

frontend/src/routes/login/alternative/device/+page.svelte

@@ -95,6 +95,11 @@
 			}
 			// Stop retrying when the server reports a non-transient failure
 			clearTimers();
+
+			if (isAxiosError(error) && error.response?.status === 401) {
+				errorMessage = m.device_login_request_expired();
+				return;
+			}
 			errorMessage = getAxiosErrorMessage(error);
 		}
 	}