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/controller/example/Relationmodel.php

@@ -0,0 +1,44 @@
+<?php
+
+namespace app\admin\controller\example;
+
+use app\common\controller\Backend;
+
+/**
+ * 关联模型
+ *
+ * @icon   fa fa-table
+ * @remark 当使用到关联模型时需要重载index方法
+ */
+class Relationmodel extends Backend
+{
+    protected $model = null;
+
+    public function _initialize()
+    {
+        parent::_initialize();
+        $this->model = model('AdminLog');
+    }
+
+    /**
+     * 查看
+     */
+    public function index()
+    {
+        $this->relationSearch = true;
+        $this->searchFields = "admin.username,id";
+        if ($this->request->isAjax()) {
+            list($where, $sort, $order, $offset, $limit) = $this->buildparams();
+            $list = $this->model
+                ->with("admin")
+                ->where($where)
+                ->order($sort, $order)
+                ->paginate($limit);
+
+            $result = array("total" => $list->total(), "rows" => $list->items());
+
+            return json($result);
+        }
+        return $this->view->fetch();
+    }
+}