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/font-awesome/bower.json

@@ -0,0 +1,22 @@
+{
+  "name": "font-awesome",
+  "description": "Font Awesome",
+  "keywords": [],
+  "homepage": "http://fontawesome.io",
+  "dependencies": {},
+  "devDependencies": {},
+  "license": ["OFL-1.1", "MIT", "CC-BY-3.0"],
+  "main": [
+    "less/font-awesome.less",
+    "scss/font-awesome.scss"
+  ],
+  "ignore": [
+    "*/.*",
+    "*.json",
+    "src",
+    "*.yml",
+    "Gemfile",
+    "Gemfile.lock",
+    "*.md"
+  ]
+}