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/GoJS-master/samples/images/project.svg

@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright 2020 by Northwoods Software -->
+<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
+<svg version="1.1" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" width="16" height="16" viewBox="0 0 16 16">
+<!-- <path fill="#000000" d="M0 0 h1 v2 h4 L9 7 h4 v-1 l2 2 -2 2 v-1 h-4 L5 13 h-4 v2 h-1 v-5 h1 v2 h4 L7.5 7.5 5 3 h-4 v1 h-1 z"></path> -->
+<path fill="#000000" d="M0 0 h2 v15 h-2 z M13 5 h2 v5 h-2 z"></path>
+<path stroke="#000000" d="M1 1 L14 6"></path>
+<path stroke="#000000" d="M1 5 L14 7"></path>
+<path stroke="#000000" d="M1 10 L14 8"></path>
+<path stroke="#000000" d="M1 14 L14 9"></path>
+</svg>