feat: 分俱乐部付呗收款通道，默认仍走微信直连

小程序前端仍传 wechat；后台可切换 wechat/fubei，支持配置多套付呗并退款按原通道路由。

Co-authored-by: Cursor <cursoragent@cursor.com>

jituan/constants.py

@@ -28,3 +28,37 @@ ADMIN_SCOPE_CLUB = 'CLUB'
 
 # 集团最高权限账号（写死超级管理员，拥有全部功能权限与集团视图）
 SUPER_ADMIN_PHONES = frozenset({'1383714110'})
+
+# —— 支付通道 ——
+PAY_CHANNEL_WECHAT_JSAPI = 'wechat_jsapi'
+PAY_CHANNEL_WECHAT_V3 = 'wechat_v3'
+PAY_CHANNEL_ALIPAY_WAP = 'alipay_wap'
+PAY_CHANNEL_FUBEI_WX_MINI = 'fubei_wx_mini'
+
+# 俱乐部「小程序收款」选用哪条通道（前端仍传 pay_method=wechat，后端按此路由）
+MINI_PAY_CHANNEL_WECHAT = 'wechat'
+MINI_PAY_CHANNEL_FUBEI = 'fubei'
+MINI_PAY_CHANNEL_CHOICES = (MINI_PAY_CHANNEL_WECHAT, MINI_PAY_CHANNEL_FUBEI)
+
+PAY_METHOD_WECHAT = 'wechat'
+PAY_METHOD_ALIPAY = 'alipay'
+PAY_METHOD_FUBEI = 'fubei'
+
+PAY_METHOD_LABELS = {
+    PAY_METHOD_WECHAT: '微信支付',
+    PAY_METHOD_ALIPAY: '支付宝',
+    PAY_METHOD_FUBEI: '微信支付',  # 前端不感知，展示仍为微信
+}
+
+PAY_METHOD_TO_CHANNEL = {
+    PAY_METHOD_WECHAT: PAY_CHANNEL_WECHAT_JSAPI,
+    PAY_METHOD_ALIPAY: PAY_CHANNEL_ALIPAY_WAP,
+    PAY_METHOD_FUBEI: PAY_CHANNEL_FUBEI_WX_MINI,
+}
+
+FUBEI_GATEWAY_PROD = 'https://shq-api.51fubei.com/gateway'
+FUBEI_GATEWAY_SANDBOX = 'https://shq-api.51fubei.com/gateway'  # 付呗文档未单独给沙箱网关时同正式
+
+# 付呗下单 biz 标记（写入 attach / 流水表，回调与退款用）
+FUBEI_BIZ_ORDER = 'order'
+FUBEI_BIZ_CZJILU = 'czjilu'