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/translate/library/google-translate-php/composer.json

@@ -0,0 +1,32 @@
+{
+    "name": "stichoza/google-translate-php",
+    "description": "Free Google Translate API PHP Package",
+    "keywords": ["google", "translate", "translator", "php"],
+    "license": "MIT",
+    "homepage": "http://github.com/Stichoza/google-translate-php",
+    "authors": [
+        {
+            "name": "Levan Velijanashvili",
+            "email": "me@stichoza.com"
+        }
+    ],
+    "require": {
+        "php": "^7.1",
+        "guzzlehttp/guzzle": "~6.0",
+        "ext-json": "*",
+        "ext-mbstring": "*"
+    },
+    "require-dev": {
+        "phpunit/phpunit": "^7.0"
+    },
+    "autoload": {
+        "psr-4": {
+            "Stichoza\\GoogleTranslate\\": "src/"
+        }
+    },
+    "autoload-dev": {
+        "psr-4": {
+            "Stichoza\\GoogleTranslate\\Tests\\": "tests/"
+        }
+    }
+}