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

addons/example/controller/Demo.php

@@ -0,0 +1,32 @@
+<?php
+
+namespace addons\example\controller;
+
+use think\addons\Controller;
+
+/**
+ * 测试控制器
+ */
+class Demo extends Controller
+{
+
+    protected $layout = 'default';
+    protected $noNeedLogin = ['index', 'demo1'];
+    protected $noNeedRight = ['*'];
+
+    public function index()
+    {
+        return $this->view->fetch();
+    }
+
+    public function demo1()
+    {
+        return $this->view->fetch();
+    }
+
+    public function demo2()
+    {
+        return $this->view->fetch();
+    }
+
+}

addons/example/controller/Index.php

@@ -0,0 +1,17 @@
+<?php
+
+namespace addons\example\controller;
+
+use think\addons\Controller;
+
+class Index extends Controller
+{
+
+    protected $layout = 'default';
+
+    public function index()
+    {
+        return $this->view->fetch();
+    }
+
+}