feat(pay): 统一收银台四种模式（站内二维码/当前页跳转/表单提交/JSAPI）

- PaymentOrchestrator 统一返回 mode + code_url/payment_url/form_html/jsapi_params
- 支付宝：当面付二维码 / 电脑网站支付 / H5；微信：Native / H5 / JSAPI（WechatOpenid 静默授权）
- 易支付：PC mapi 二维码，移动端自动提交表单
- 删除旧键 alipay_payment_type / wechat_payment_type / epay_device 与 redirect/qr_content 字段
- 新增 pay-cashier.js，移除 window.open，订单状态接口改为 /pay/order/{n}
- 拆分 credits.js（affiliate / withdraw-history）至 1000 行以内

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

assets/js/pay-vip.js

@@ -577,7 +577,9 @@
       tags: ["vip", "orders"],
       onPending: function (data) {
         waitingPayment = true;
-        if (data.payment_url) window.open(data.payment_url, "_blank");
+        if (window.AksrtPayCashier) {
+          window.AksrtPayCashier.handle(data, { onClose: cancelActivePurchase });
+        }
         notyf(data.message || "请完成支付，支付成功后将自动刷新。", "info", 5, activePurchaseToastId);
         activePurchaseToastId = "aksrt-vip-payment-toast";
         notyf("等待支付结果…", "load", "", activePurchaseToastId);
@@ -831,16 +833,22 @@
     vipPay(trigger);
   }
 
-  document.addEventListener("aksrt:modal:close", function (event) {
-    var detail = event && event.detail ? event.detail : {};
-    var options = detail.session && detail.session.options ? detail.session.options : {};
-    if (options.kind !== "vip" || !activePurchase) return;
+  function cancelActivePurchase() {
+    if (!activePurchase) return;
     if (typeof activePurchase.abort === "function") activePurchase.abort();
     activePurchase = null;
     if (activePurchaseToastId) {
       notyf("已取消会员购买", "warning", 3, activePurchaseToastId);
       activePurchaseToastId = "";
     }
+  }
+
+  // VIP 弹窗被收银二维码弹窗替换（reason=replace）时保持轮询；用户主动关闭才取消。
+  document.addEventListener("aksrt:modal:close", function (event) {
+    var detail = event && event.detail ? event.detail : {};
+    var options = detail.session && detail.session.options ? detail.session.options : {};
+    if (options.kind !== "vip" || detail.reason === "replace") return;
+    cancelActivePurchase();
   });
 
   // 积分兑换入口（data-aksrt-vip-points-open）文档级委托：一处绑定同时覆盖