add copy

package.json

@@ -16,6 +16,7 @@
     "@vueuse/core": "^12.8.2",
     "axios": "^1.8.1",
     "codemirror": "^6.0.1",
+    "copy-text-to-clipboard": "^3.2.0",
     "github-markdown-css": "^5.8.1",
     "highlight.js": "^11.11.1",
     "marked": "^15.0.7",