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

public/assets/css/user.css

@@ -0,0 +1,73 @@
+h2.page-header {
+  margin: 10px 0 25px 0;
+  padding-bottom: 15px;
+}
+.user-baseinfo {
+  margin-bottom: 25px;
+}
+.user-baseinfo table tr td {
+  color: #999;
+}
+@media (min-width: 992px) {
+  .user-center .avatar-text,
+  .user-center .avatar-img {
+    height: 150px;
+    width: 150px;
+    border-radius: 150px;
+    line-height: 150px;
+    font-size: 70px;
+  }
+  .user-center .avatar-img {
+    font-size: 0;
+  }
+  .user-center .avatar-img img {
+    height: 150px;
+    width: 150px;
+    border-radius: 150px;
+  }
+}
+.sidebar-toggle {
+  display: none;
+}
+@media (max-width: 991px) {
+  .sidenav {
+    position: fixed;
+    top: 50px;
+    z-index: 1029;
+    height: calc(100vh - 50px);
+    padding: 20px 0 20px 0;
+    min-width: 250px;
+    overflow-y: auto;
+    overflow-x: hidden;
+    width: 250px;
+    left: -250px;
+    -webkit-transition: all 0.3s ease;
+    -moz-transition: all 0.3s ease;
+    -o-transition: all 0.3s ease;
+    transition: all 0.3s ease;
+  }
+  .sidebar-toggle {
+    display: block;
+    position: fixed;
+    right: 20px;
+    bottom: 70px;
+    border-radius: 50%;
+    background: #eee;
+    font-size: 22px;
+    padding: 10px;
+    line-height: 30px;
+    height: 50px;
+    width: 50px;
+    text-align: center;
+    z-index: 999999;
+  }
+}
+body.sidebar-open .sidenav {
+  left: 0;
+  width: 250px;
+  box-shadow: 0 6px 27px rgba(0, 0, 0, 0.075);
+}
+body.sidebar-open .sidebar-toggle i:before {
+  content: "\f00d";
+}
+/*# sourceMappingURL=user.css.map */