feat: bepusdt支付渠道增加钱包地址显示和复制功能

- 后端: 添加wallet_address字段到支付信息返回
- 前端: Checkout页面显示钱包地址，支持点击复制

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

backend/internal/api/handlers/payment.go

@@ -156,6 +156,7 @@ func (h *PaymentHandler) CreatePayment(c *gin.Context) {
 	tradeID, _ := data["trade_id"].(string)
 	token, _ := data["token"].(string)
 	paymentURL, _ := data["payment_url"].(string)
+	walletAddress, _ := data["address"].(string)
 
 	var amount float64
 	if v, ok := data["amount"].(float64); ok {
@@ -207,6 +208,7 @@ func (h *PaymentHandler) CreatePayment(c *gin.Context) {
 		"actual_amount":   actualAmount,
 		"token":           token,
 		"payment_url":     paymentURL,
+		"wallet_address":  walletAddress,
 		"expiration_time": remainingSeconds,
 		"trade_type":      tradeType,
 		"channel_id":      channel.ID,

frontend/src/views/user/Checkout.vue

@@ -33,6 +33,21 @@
         <div class="qr-tip">请使用手机浏览器扫码完成支付</div>
       </div>
 
+      <div class="address-section" v-if="paymentInfo.wallet_address">
+        <div class="address-label">
+          <span>钱包地址</span>
+          <span class="network-tag">{{ paymentInfo.trade_type?.toUpperCase() }}</span>
+        </div>
+        <div class="address-box">
+          <span class="address-text">{{ paymentInfo.wallet_address }}</span>
+          <el-button type="primary" size="small" @click="copyAddress">
+            <el-icon><CopyDocument /></el-icon>
+            复制
+          </el-button>
+        </div>
+        <div class="address-tip">请勿向此地址转账其他资产，否则将无法找回</div>
+      </div>
+
       <div class="tips">
         <p>1. 请使用 {{ paymentInfo.trade_type?.toUpperCase() }} 网络转账</p>
         <p>2. 请准确转账 <strong>{{ paymentInfo.actual_amount || paymentInfo.amount }} USDT</strong></p>
@@ -66,7 +81,7 @@
 import { ref, onMounted, onUnmounted } from 'vue'
 import { useRoute, useRouter } from 'vue-router'
 import { ElMessage } from 'element-plus'
-import { Loading, CircleCloseFilled } from '@element-plus/icons-vue'
+import { Loading, CircleCloseFilled, CopyDocument } from '@element-plus/icons-vue'
 import { orderApi } from '../../api'
 import QRCode from 'qrcode'
 
@@ -124,6 +139,13 @@ function startCountdown() {
   }, 1000)
 }
 
+function copyAddress() {
+  if (paymentInfo.value?.wallet_address) {
+    navigator.clipboard.writeText(paymentInfo.value.wallet_address)
+    ElMessage.success('地址已复制到剪贴板')
+  }
+}
+
 function startPolling() {
   pollTimer = setInterval(async () => {
     try {
@@ -264,6 +286,57 @@ onUnmounted(() => {
   }
 }
 
+.address-section {
+  width: 100%;
+  margin-bottom: 24px;
+
+  .address-label {
+    display: flex;
+    align-items: center;
+    gap: 8px;
+    font-size: 13px;
+    color: rgba(255, 255, 255, 0.5);
+    margin-bottom: 12px;
+
+    .network-tag {
+      background: rgba(38, 161, 123, 0.15);
+      color: #26a17b;
+      padding: 2px 8px;
+      border-radius: 4px;
+      font-size: 11px;
+      font-weight: 600;
+    }
+  }
+
+  .address-box {
+    display: flex;
+    align-items: center;
+    gap: 12px;
+    background: rgba(255, 255, 255, 0.06);
+    border: 1px solid rgba(255, 255, 255, 0.08);
+    border-radius: 8px;
+    padding: 12px 16px;
+
+    .address-text {
+      flex: 1;
+      font-size: 14px;
+      color: #fff;
+      word-break: break-all;
+      font-family: monospace;
+    }
+
+    .el-button {
+      flex-shrink: 0;
+    }
+  }
+
+  .address-tip {
+    font-size: 12px;
+    color: rgba(245, 158, 11, 0.8);
+    margin-top: 8px;
+  }
+}
+
 .tips {
   width: 100%;
   background: rgba(255, 255, 255, 0.03);