```后台: 新增用户搜索功能并优化进件页面UI

- 在Onboard控制器中添加searchUser方法，支持按昵称、手机号、ID搜索用户
- 修改noNeedRight权限配置，添加searchUser访问权限
- 重构用户选择逻辑，使用新的fetchUserPublic和formatUserOption方法
- 实现用户搜索功能，支持关键词模糊匹配并返回格式化的用户选项
- 优化前端页面样式，采用卡片式布局提升用户体验
- 添加用户头像显示和个人信息展示功能
- 调整页面结构，增加标题栏、底部操作栏等组件
```

application/admin/controller/shopro_huifu/Onboard.php

@@ -13,7 +13,7 @@ use app\admin\controller\shopro\Base;
 
 class Onboard extends Base
 {
-    protected $noNeedRight = ['userRoles', 'searchBranch'];
+    protected $noNeedRight = ['userRoles', 'searchUser', 'searchBranch'];
     public function index()
     {
         if ($this->request->isAjax()) {
@@ -108,17 +108,22 @@ class Onboard extends Base
         if ($userId <= 0) {
             $this->error('请选择用户');
         }
-        $user = HuifuOnboardAdminView::enrichListRow(['user_id' => $userId, 'payload' => '']);
+        $userRow = HuifuOnboardAdminView::fetchUserPublic($userId);
         $this->success('ok', null, [
-            'user' => [
-                'id' => $userId,
-                'nickname' => $user['user_nickname'] ?? '',
-                'mobile' => $user['user_mobile'] ?? '',
-            ],
+            'user' => HuifuOnboardAdminView::formatUserOption($userRow),
             'roles' => HuifuOnboardAdminView::listRolesForUser($userId),
         ]);
     }
 
+    public function searchUser()
+    {
+        $keyword = trim((string) $this->request->get('keyword', ''));
+        if ($keyword === '') {
+            $this->success('ok', null, []);
+        }
+        $this->success('ok', null, HuifuOnboardAdminView::searchUsers($keyword, intval($this->request->get('limit', 20))));
+    }
+
     public function searchBranch()
     {
         $keyword = trim((string) $this->request->get('keyword', ''));