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>

nginx.conf

@@ -5,6 +5,24 @@ server {
     root /usr/share/nginx/html;
     index index.html;
 
+    # 后端接口反向代理；Docker 启动时由 API_UPSTREAM 注入，例如：http://host.docker.internal:3000
+    location /api/ {
+        proxy_pass ${API_UPSTREAM};
+        proxy_http_version 1.1;
+
+        proxy_set_header Host $host;
+        proxy_set_header X-Real-IP $remote_addr;
+        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
+        proxy_set_header X-Forwarded-Proto $scheme;
+
+        proxy_set_header Upgrade $http_upgrade;
+        proxy_set_header Connection "upgrade";
+
+        proxy_read_timeout 300s;
+        proxy_send_timeout 300s;
+        proxy_buffering off;
+    }
+
     # Vite build 产物：文件名带 hash，可长期缓存
     location /assets/ {
         expires 1y;