修复刷卡/并充余额校验问题：余额不足默认充电金额时改用全部余额，而非直接拒绝启动充电

- ConfirmStartChargingRequestHandler: 云快充刷卡预校验，余额小于默认金额时降级为全部余额
- resolveBalanceChargeAmount: 订单生成共享校验方法，余额不足默认金额时降级为全部余额
- 并充生成订单: 同逻辑修复
- 扫码支付（NotDelayMerchant/DelayMerchant）不受影响，独立的余额校验逻辑保持不变

jsowell-netty/src/main/java/com/jsowell/netty/handler/yunkuaichong/ConfirmStartChargingRequestHandler.java

@@ -317,7 +317,13 @@ public class ConfirmStartChargingRequestHandler extends AbstractYkcHandler {
             BigDecimal totalBalance = memberWalletVO.getTotalBalance() == null
                     ? BigDecimal.ZERO
                     : memberWalletVO.getTotalBalance();
-            if (!ChargeAmountUtils.isPositive(chargeAmount) || totalBalance.compareTo(chargeAmount) < 0) {
+            // 账户余额小于默认充电金额时，使用全部余额
+            if (totalBalance.compareTo(chargeAmount) < 0) {
+                log.info("余额不足默认金额，使用全部余额, memberId:{}, chargeAmount:{}, totalBalance:{}",
+                        memberWalletVO.getMemberId(), chargeAmount, totalBalance);
+                chargeAmount = totalBalance;
+            }
+            if (!ChargeAmountUtils.isPositive(chargeAmount)) {
                 log.info("余额不足, memberId:{}, chargeAmount:{}, totalBalance:{}",
                         memberWalletVO.getMemberId(), chargeAmount, totalBalance);
                 return buildFailureResult("03");