Function _apply_env_change

app/admin/config_manager.py:593–616

(
    writer: Callable[[Path], None],
    *,
    reload_callback: ReloadCallback,
    env_path: str | Path = ENV_PATH,
)

async def _apply_env_change(
    writer: Callable[[Path], None],
    *,
    reload_callback: ReloadCallback,
    env_path: str | Path = ENV_PATH,
) -> None:
    path = Path(env_path)
    had_existing_file = path.exists()
    previous_content = read_env_content(path) if had_existing_file else ""

    try:
        writer(path)
        await reload_callback()
    except Exception:
        if had_existing_file:
            path.write_text(previous_content, encoding="utf-8")
        elif path.exists():
            path.unlink()

        try:
            await reload_callback()
        except Exception as restore_exc:
            logger.warning(f"⚠️ 回滚配置后重新加载失败: {restore_exc}")
        raise


async def save_form_config(