fix: 修复issue，COPY-01 复制直链功能 FAILED 控制台报错：Cannot read properties of undefined (reading 'writeText') 剪贴板API兼容性问题、改进剪贴板复制功能以兼容旧浏览器

添加对旧浏览器的兼容性处理，当navigator.clipboard不可用时，使用document.execCommand作为备选方案

script.js

@@ -298,7 +298,35 @@ function copyDirectLink(appId, fileName) {
     const directLink = `${API_BASE_URL}/apps/${appId}`; // 生成直链URL
     
     // 复制到剪贴板
-    navigator.clipboard.writeText(directLink)
+    const copyToClipboard = (text) => {
+        if (navigator.clipboard && navigator.clipboard.writeText) {
+            return navigator.clipboard.writeText(text);
+        } else {
+            return new Promise((resolve, reject) => {
+                const textarea = document.createElement('textarea');
+                textarea.value = text;
+                textarea.style.position = 'fixed';
+                textarea.style.opacity = '0';
+                document.body.appendChild(textarea);
+                textarea.select();
+                
+                try {
+                    const successful = document.execCommand('copy');
+                    document.body.removeChild(textarea);
+                    if (successful) {
+                        resolve();
+                    } else {
+                        reject(new Error('复制命令执行失败'));
+                    }
+                } catch (err) {
+                    document.body.removeChild(textarea);
+                    reject(err);
+                }
+            });
+        }
+    };
+    
+    copyToClipboard(directLink)
         .then(() => {
             // 显示复制成功提示
             const message = document.createElement('div');