feat: 功能3 - Markdown 渲染和代码高亮 (v0.9.8)

- 添加 MarkdownMessage.vue 组件
- 集成 markdown-it 库
- 集成 highlight.js 代码高亮
- 支持标题/列表/代码块/表格等
- ChatWindow 使用 Markdown 渲染
- 添加 .gitignore 忽略 node_modules

frontend/package.json

@@ -9,15 +9,15 @@
     "typecheck": "vue-tsc --noEmit"
   },
   "dependencies": {
-    "vue": "^3.4.0",
-    "vue-router": "^4.2.0",
+    "@highlightjs/vue-plugin": "^2.1.0",
+    "axios": "^1.6.0",
+    "date-fns": "^3.0.0",
+    "highlight.js": "^11.11.1",
+    "markdown-it": "^14.1.1",
     "pinia": "^2.1.0",
     "socket.io-client": "^4.7.0",
-    "axios": "^1.6.0",
-    "markdown-it": "^14.0.0",
-    "highlight.js": "^11.9.0",
-    "@highlightjs/vue-plugin": "^2.1.0",
-    "date-fns": "^3.0.0"
+    "vue": "^3.4.0",
+    "vue-router": "^4.2.0"
   },
   "devDependencies": {
     "@vitejs/plugin-vue": "^5.0.0",