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/learn/kod/static/others/app/manifest.json

@@ -0,0 +1,25 @@
+{
+    "name": "{{name}}",
+    "short_name": "{{name}}",
+    "description": "{{appDesc}}",
+    "icons": [
+        {
+            "src": "{{static}}others/app/icon/icon_192.png",
+            "sizes": "192x192",
+            "type": "image/png"
+        },
+        {
+            "src": "{{static}}others/app/icon/icon_512.png",
+            "sizes": "512x512",
+            "type": "image/png"
+        }
+    ],
+    "start_url": "./",
+    "scope": "./",
+    "display": "standalone",
+    "orientation": "portrait",
+    "background_color": "#F3F3F3",
+    "theme_color": "#1b6de1",
+    "related_applications": [],
+    "prefer_related_applications": false
+}

public/GoJS-master/learn/kod/static/others/app/sw.js

@@ -0,0 +1,9 @@
+const cacheName = 'kodcloud';
+const staticAssets = [];
+self.addEventListener('install', async e => {
+});
+self.addEventListener('activate', e => {
+    self.clients.claim();
+});
+self.addEventListener('fetch', async e => {
+});