fix(desktop): increase backend readiness timeout to 3 minutes

apps/desktop/src/backend/DesktopBackendManager.ts

@@ -60,7 +60,10 @@ const MAX_RESTART_DELAY = Duration.seconds(10);
 // failures may instead provide their own larger retryLimit when they should
 // self-heal for a while but must not leave the app connecting forever.
 const MAX_PREFLIGHT_FAILURE_ATTEMPTS = 5;
-const DEFAULT_BACKEND_READINESS_TIMEOUT = Duration.minutes(1);
+// WSL backends can take well over a minute to become ready when the packaged
+// server bundle is loaded through /mnt/c (see #4535). Readiness polling still
+// resolves as soon as the endpoint responds, so fast backends are unaffected.
+const DEFAULT_BACKEND_READINESS_TIMEOUT = Duration.minutes(3);
 const DEFAULT_BACKEND_READINESS_INTERVAL = Duration.millis(100);
 const DEFAULT_BACKEND_READINESS_REQUEST_TIMEOUT = Duration.seconds(1);
 const DEFAULT_BACKEND_TERMINATE_GRACE = Duration.seconds(2);