feat: AI routing DB-driven, payment gateway full integration, WeChat mini-program CI/CD

- AI routing rules now stored in system_configs DB table instead of hardcoded config
- Multi-model support via name|model composite key for same-provider routing
- UnifiedPayService with HMAC-SHA256 gateway integration (alipay/wechat)
- Admin payment panel: list, stats, search, filter, refund
- WeChat mini-program CI/CD via miniprogram-ci (v1.0.9)
- Translation quota extended to LLM provider tier
- SearchService with DB-driven provider config (bing/google_cse/searxng)
- Footer cleanup across admin/workspace/uni-app
- Private key excluded from git tracking

uni-app/src/utils/api.js

@@ -1,6 +1,12 @@
 import { STORAGE_KEYS, PAGES } from '@/config.js'
 
-export const BASE_URL = '/api/v1'
+// #ifdef MP-WEIXIN
+const API_HOST = 'https://trade.yuzhiran.com'
+// #endif
+// #ifndef MP-WEIXIN
+const API_HOST = ''
+// #endif
+export const BASE_URL = `${API_HOST}/api/v1`
 
 const getAuthHeader = () => {
   const token = uni.getStorageSync(STORAGE_KEYS.TOKEN)