fix: waits for startup by markers instead of timer

src/claude_code_api/backend.py

@@ -81,7 +81,7 @@ class BackendOptions:
     history_injection_mode: HistoryInjectionMode = "native_jsonl"
     wait_for_turn_duration: bool = False
     include_meta_user: bool = False
-    startup_delay: float = 1.0
+    startup_delay: float = 10.0
     file_wait_timeout: float = 30.0
     turn_duration_timeout: float = 5.0