feat(ui): 统一登录与会话页的 shadcn 交互组件

登录页切换为官方 input-group 组合并将全站提示从 antd message 统一为 sonner toast，确保通知位置与风格一致。同时补齐相关 shadcn CLI 生成组件及构建配置更新。

Co-authored-by: Cursor <cursoragent@cursor.com>

package.json

@@ -25,12 +25,17 @@
     "*.{css,json,md,html,yml,yaml,js,mjs,cjs}": "prettier --write"
   },
   "dependencies": {
+    "@fontsource-variable/geist": "^5.2.8",
     "@microsoft/fetch-event-source": "^2.0.1",
     "antd": "^6.3.5",
     "axios": "^1.15.0",
+    "class-variance-authority": "^0.7.1",
+    "clsx": "^2.1.1",
     "highlight.js": "^11.11.1",
     "katex": "^0.16.45",
-    "lucide-react": "^1.9.0",
+    "lucide-react": "^1.14.0",
+    "next-themes": "^0.4.6",
+    "radix-ui": "^1.4.3",
     "react": "^19.2.4",
     "react-dom": "^19.2.4",
     "react-markdown": "^10.1.0",
@@ -38,7 +43,11 @@
     "rehype-highlight": "^7.0.2",
     "rehype-katex": "^7.0.1",
     "remark-gfm": "^4.0.1",
-    "remark-math": "^6.0.0"
+    "remark-math": "^6.0.0",
+    "shadcn": "^4.7.0",
+    "sonner": "^2.0.7",
+    "tailwind-merge": "^3.6.0",
+    "tw-animate-css": "^1.4.0"
   },
   "devDependencies": {
     "@eslint/js": "^10.0.1",
@@ -60,5 +69,6 @@
     "typescript-eslint": "^8.58.0",
     "vite": "^8.0.3",
     "vite-plugin-pages": "^0.33.3"
-  }
+  },
+  "packageManager": "yarn@4.14.1"
 }