support vscode naive-ui doc copy

[Simon-He95]

This function solves the problem (这个功能解决的问题)

I want to open doc in vscode webview，it will be more helpful to solve the problem of frequent switching between browsers and vscode

Expected API (期望的 API)

document.addEventListener('keydown', e => {
if ((e.metaKey || e.ctrlKey) && e.key === 'c') {
const selection = document.getSelection();
if (!selection || !selection.toString()) return;
const text = selection.toString();
window.parent.postMessage({ eventType: 'copy', text }, '*');
}
});