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

thinkphp/composer.json

@@ -0,0 +1,35 @@
+{
+    "name": "topthink/framework",
+    "description": "the new thinkphp framework",
+    "type": "think-framework",
+    "keywords": [
+        "framework",
+        "thinkphp",
+        "ORM"
+    ],
+    "homepage": "http://thinkphp.cn/",
+    "license": "Apache-2.0",
+    "authors": [
+        {
+            "name": "liu21st",
+            "email": "liu21st@gmail.com"
+        }
+    ],
+    "require": {
+        "php": ">=5.4.0",
+        "topthink/think-installer": "~1.0"
+    },
+    "require-dev": {
+        "phpunit/phpunit": "4.8.*",
+        "johnkary/phpunit-speedtrap": "^1.0",
+        "mikey179/vfsStream": "~1.6",
+        "phploc/phploc": "2.*",
+        "sebastian/phpcpd": "2.*",
+        "phpdocumentor/reflection-docblock": "^2.0"
+    },
+    "autoload": {
+        "psr-4": {
+            "think\\": "library/think"
+        }
+    }
+}