拆分 AccountCenter 超大组件：提取类型、常量、钱包、支付等独立模块

- AccountCenter.tsx 从 3565 行缩减约 1000 行
- 新增 8 个模块：types / constants / formatters / account-copy / wallet / payment-utils / usePaymentState / AccountInfoRow
- 同步更新 paymentShell 测试

Confidence: high

frontend/components/account/AccountInfoRow.tsx

@@ -0,0 +1,51 @@
+import type { LucideIcon } from "lucide-react";
+
+type InfoRowProps = {
+  icon?: LucideIcon;
+  label: string;
+  value: string;
+  isPrimary?: boolean;
+};
+
+export const InfoRow = ({
+  icon: Icon,
+  label,
+  value,
+  isPrimary = false,
+}: InfoRowProps) => (
+  <div className="flex min-w-0 flex-col gap-3 p-4 bg-white/5 rounded-2xl border border-white/5 hover:bg-white/10 transition-all group sm:flex-row sm:items-center sm:justify-between">
+    <div className="flex min-w-0 items-center gap-3">
+      <div className="shrink-0 p-2 bg-slate-800 rounded-lg text-slate-400 group-hover:text-blue-400 transition-colors">
+        {Icon && <Icon size={18} />}
+      </div>
+      <span className="min-w-0 text-slate-400 text-sm font-medium leading-5">
+        {label}
+      </span>
+    </div>
+    <span
+      className={`min-w-0 break-all text-left text-sm font-semibold font-mono sm:text-right ${isPrimary ? "text-blue-400" : "text-slate-200"}`}
+    >
+      {value}
+    </span>
+  </div>
+);
+
+
+export function PlusIcon({ className }: { className?: string }) {
+  return (
+    <svg
+      className={className}
+      width="24"
+      height="24"
+      viewBox="0 0 24 24"
+      fill="none"
+      stroke="currentColor"
+      strokeWidth="2"
+      strokeLinecap="round"
+      strokeLinejoin="round"
+    >
+      <line x1="12" y1="5" x2="12" y2="19"></line>
+      <line x1="5" y1="12" x2="19" y2="12"></line>
+    </svg>
+  );
+}