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>

src/components/StreamMessage.tsx

@@ -1,11 +1,12 @@
 import { useState } from "react";
-import { Button, message } from "antd";
+import { Button } from "antd";
 import { Check, Copy } from "lucide-react";
 import ReactMarkdown from "react-markdown";
 import remarkGfm from "remark-gfm";
 import remarkMath from "remark-math";
 import rehypeKatex from "rehype-katex";
 import rehypeHighlight from "rehype-highlight";
+import { toast } from "sonner";
 import "katex/dist/katex.min.css";
 import "highlight.js/styles/github.css";
 import type { ReactNode } from "react";
@@ -34,10 +35,10 @@ function MarkdownPreBlock(props: { children: ReactNode }) {
     try {
       await navigator.clipboard.writeText(codeText);
       setCopied(true);
-      message.success("代码已复制");
+      toast.success("代码已复制");
       window.setTimeout(() => setCopied(false), 1200);
     } catch {
-      message.error("复制失败");
+      toast.error("复制失败");
     }
   };