feat: 后端全量更新 - 含所有本次需求

- Contract.php: 返回合约账户余额(balance_contract)
- My.php: 地址管理增加BTC/ETH
- AppContract.php: 一键平仓(closeall)
- AppProxy.php: 代理专属注册链接 + 分级权限(L1/L2)
- site.php: 手续费减半(0.018→0.009)
- agent_permission_setup.sql: 代理权限SQL
- crypto_news_crawler.py: 新闻自动采集脚本

application/admin/command/Crud/stubs/controllerindex.stub

@@ -0,0 +1,34 @@
+
+    /**
+     * 查看
+     */
+    public function index()
+    {
+        //当前是否为关联查询
+        $this->relationSearch = {%relationSearch%};
+        //设置过滤方法
+        $this->request->filter(['strip_tags', 'trim']);
+        if ($this->request->isAjax()) {
+            //如果发送的来源是Selectpage，则转发到Selectpage
+            if ($this->request->request('keyField')) {
+                return $this->selectpage();
+            }
+            list($where, $sort, $order, $offset, $limit) = $this->buildparams();
+
+            $list = $this->model
+                    {%relationWithList%}
+                    ->where($where)
+                    ->order($sort, $order)
+                    ->paginate($limit);
+
+            foreach ($list as $row) {
+                {%visibleFieldList%}
+                {%relationVisibleFieldList%}
+            }
+
+            $result = array("total" => $list->total(), "rows" => $list->items());
+
+            return json($result);
+        }
+        return $this->view->fetch();
+    }