fix: 远程http访问时复制Cookie失败，添加execCommand fallback兼容非安全上下文

web/frontend/src/pages/CookiePage.tsx

@@ -8,6 +8,30 @@ import { getErrorMessage } from '../utils/error';
 
 const { Text } = Typography;
 
+/** 复制文本到剪贴板，兼容非安全上下文（http://非localhost） */
+function copyToClipboard(text: string): Promise<void> {
+  if (navigator.clipboard?.writeText) {
+    return navigator.clipboard.writeText(text);
+  }
+  // fallback：利用 textarea + execCommand，兼容 http 远程访问
+  return new Promise((resolve, reject) => {
+    const ta = document.createElement('textarea');
+    ta.value = text;
+    ta.style.position = 'fixed';
+    ta.style.left = '-9999px';
+    document.body.appendChild(ta);
+    ta.select();
+    try {
+      const ok = document.execCommand('copy');
+      document.body.removeChild(ta);
+      ok ? resolve() : reject(new Error('execCommand copy failed'));
+    } catch (e) {
+      document.body.removeChild(ta);
+      reject(e);
+    }
+  });
+}
+
 export default function CookiePage() {
   const { token } = theme.useToken();
   const [cookies, setCookies] = useState<CookieItem[]>([]);
@@ -55,7 +79,7 @@ export default function CookiePage() {
       message.warning('Cookie 为空');
       return;
     }
-    navigator.clipboard.writeText(cookie).then(() => {
+    copyToClipboard(cookie).then(() => {
       message.success(`已复制 ${username} 的 Cookie`);
     }).catch(() => {
       message.error('复制失败');
@@ -71,7 +95,7 @@ export default function CookiePage() {
     const text = selected
       .map((c) => `${c.account_username}: ${c.cookie || '(空)'}`)
       .join('\n');
-    navigator.clipboard.writeText(text).then(() => {
+    copyToClipboard(text).then(() => {
       message.success(`已复制 ${selected.length} 条 Cookie`);
     }).catch(() => {
       message.error('复制失败');