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/libs/fastadmin-layer/package.json

@@ -0,0 +1,41 @@
+{
+  "name": "layui-layer",
+  "realname": "layer",
+  "version": "3.1.5",
+  "mobile": "2.0.0",
+  "description": "Web弹层组件",
+  "main": "src/layer.js",
+  "license": "MIT",
+  "scripts": {
+    "run": "gulp"
+  },
+  "repository": {
+    "type": "https",
+    "url": "git+https://github.com/sentsin/layer.git"
+  },
+  "author": "贤心",
+  "homepage": "http://layer.layui.com/",
+  "devDependencies": {
+    "del": "~2.2.2",
+    "gulp": "^4.0.2",
+    "gulp-header": "~1.8.8",
+    "gulp-clean-css": "~4.2.0",
+    "gulp-rename": "~1.2.2",
+    "gulp-uglify": "~1.5.4"
+  },
+  "bugs": {
+    "url": "https://github.com/sentsin/layer/issues"
+  },
+  "directories": {
+    "test": "test"
+  },
+  "dependencies": {},
+  "keywords": [
+    "layer",
+    "dialog",
+    "tips",
+    "alert",
+    "confirm",
+    "window"
+  ]
+}