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/Customsearch.php

@@ -0,0 +1,24 @@
+<?php
+
+namespace app\admin\controller\example;
+
+use app\common\controller\Backend;
+
+/**
+ * 自定义搜索
+ *
+ * @icon fa fa-search
+ * @remark 自定义列表的搜索
+ */
+class Customsearch extends Backend
+{
+    protected $model = null;
+
+    public function _initialize()
+    {
+        parent::_initialize();
+        $this->model = model('AdminLog');
+        $ipList = $this->model->whereTime('createtime', '-37 days')->group("ip")->column("ip,ip as aa");
+        $this->view->assign("ipList", $ipList);
+    }
+}