feat(tenant-balance): 新增提现站内信通知功能

在提现流程中，向租户联系人发送站内信通知，模板码 tx-001，携带提现金额参数。

keyboard-server/src/main/java/com/yolo/keyboard/service/tenantbalance/TenantBalanceServiceImpl.java

@@ -10,6 +10,8 @@ import com.yolo.keyboard.framework.common.util.collection.CollectionUtils;
 import com.yolo.keyboard.framework.mybatis.core.query.LambdaQueryWrapperX;
 import com.yolo.keyboard.framework.tenant.core.context.TenantContextHolder;
 import com.yolo.keyboard.module.infra.api.config.ConfigApi;
+import com.yolo.keyboard.module.system.api.notify.NotifyMessageSendApi;
+import com.yolo.keyboard.module.system.api.notify.dto.NotifySendSingleToUserReqDTO;
 import com.yolo.keyboard.utils.BizNoGenerator;
 import org.springframework.stereotype.Service;
 import jakarta.annotation.Resource;
@@ -59,7 +61,11 @@ public class TenantBalanceServiceImpl implements TenantBalanceService {
     @Resource
     private KeyboardTenantWithdrawOrderMapper tenantWithdrawOrderMapper;
 
+    @Resource
+    private NotifyMessageSendApi notifyMessageSendApi;
+
     private static final String WITHDRAW_DAYS_CONFIG_KEY = "WITHDRAW-DAYS";
+    private static final String WITHDRAW_NOTIFY_TEMPLATE_CODE = "tx-001";
 
     @Override
     public Long createTenantBalance(TenantBalanceSaveReqVO createReqVO) {
@@ -300,6 +306,32 @@ public class TenantBalanceServiceImpl implements TenantBalanceService {
                 .updatedAt(now)
                 .build();
         tenantWithdrawOrderMapper.insert(withdrawOrder);
+
+        // 8. 发送站内信通知
+        sendWithdrawNotify(tenantId, withdrawAmount);
+    }
+
+    /**
+     * 发送提现站内信通知
+     *
+     * @param tenantId       租户ID
+     * @param withdrawAmount 提现金额
+     */
+    private void sendWithdrawNotify(Long tenantId, BigDecimal withdrawAmount) {
+        // 获取租户信息，找到联系人用户ID
+        TenantDO tenant = tenantMapper.selectById(tenantId);
+        if (tenant == null || tenant.getContactUserId() == null) {
+            return;
+        }
+
+        // 构建站内信请求
+        NotifySendSingleToUserReqDTO reqDTO = new NotifySendSingleToUserReqDTO();
+        reqDTO.setUserId(tenant.getContactUserId());
+        reqDTO.setTemplateCode(WITHDRAW_NOTIFY_TEMPLATE_CODE);
+        reqDTO.setTemplateParams(Map.of("amount", withdrawAmount.toPlainString()));
+
+        // 发送站内信
+        notifyMessageSendApi.sendSingleMessageToAdmin(reqDTO);
     }
 
     /**