useSize在乾坤微前端做了多tab的keepAlive时候 子应用的 DOM 节点可能已经被销毁或重新挂载，导致 ResizeObserver 监听的节点失效 直接白屏

## 报错信息：
TypeError: undefined is not iterable (cannot read property Symbol(Symbol.iterator))
## 解决思路
```tsx
import { useState, useEffect } from 'react';

export const useSize = (domRef: React.RefObject) => {
const [size, setSize] = useState({ width: 0, height: 0 });

useEffect(() => {
const element = domRef.current;

if (!element) {
console.warn('`useSize`: domRef is null or undefined.');
return;
}

if (typeof ResizeObserver === 'undefined') {
console.warn('`useSize`: ResizeObserver is not supported by this browser.');
return;
}

let isMounted = true; // 防止卸载后更新状态
const observer = new ResizeObserver(entries => {
if (!isMounted) return;

try {
const entry = entries[0];
if (entry && entry.target.isConnected) {
const { width, height } = entry.contentRect;
setSize({ width, height });
}
} catch (error) {
console.error('`useSize`: Error in ResizeObserver callback.', error);
}
});

observer.observe(element);

return () => {
isMounted = false;
observer.disconnect(); // 确保在卸载时断开监听
};
}, [domRef]);

return size;
};
```

Locate the useSize hook implementation and first reproduce the reported failure when a kept-alive micro-frontend tab destroys or remounts its DOM node. Check the ResizeObserver callback and lifecycle handling, then verify that the hook no longer causes a blank screen when the referenced element is missing or disconnected.

Written by the indexing model from the issue text.