🎨 1.优化前端渲染功能（html和对话消息格式）

2.优化流式传输，新增流式渲染功能
3.优化正则处理逻辑
4.新增context budget管理系统
5.优化对话消息失败处理逻辑
6.新增前端卡功能（待完整测试）

web-app/package.json

@@ -10,6 +10,7 @@
   },
   "dependencies": {
     "axios": "^1.13.5",
+    "js-yaml": "^4.1.1",
     "lucide-react": "^0.344.0",
     "react": "^18.3.1",
     "react-dom": "^18.3.1",
@@ -21,6 +22,7 @@
     "zustand": "^5.0.11"
   },
   "devDependencies": {
+    "@types/js-yaml": "^4.0.9",
     "@types/react": "^18.3.3",
     "@types/react-dom": "^18.3.0",
     "@vitejs/plugin-react": "^4.3.1",