fix: 停复机指令队列审查问题

- 开关开启但分发器心跳缺失时回退为当场执行，避免指令无人消费
- 待确认指令先查上游状态再判断；执行期间被覆盖时把待确认带到新指令
- 同方向失败退避中重复写入不提前执行时间
- 领取容量把执行上限与本秒剩余 QPS 分开计算
- 队列复机共用单卡复机锁；执行上下文取消后按结果未知确认
- 消费者并行停止；读取最近调用时间失败时不覆盖；成功但终结日志失败按成功处理

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

internal/polling/carrierqueue/sr_dispatch.go

@@ -42,29 +42,30 @@ func (d *Dispatcher) stopResumeLease() time.Duration {
 // dispatchStopResume 在卡任务之前领取账户停复机指令：领取数 = min(停复机所在限流组本秒剩余, 执行上限 − 执行中)。
 func (d *Dispatcher) dispatchStopResume(ctx context.Context, carrierID uint) {
 	params := d.ParamsFor(carrierID)
-	capacity := params.SRInflightLimit
+	limit := params.SRInflightLimit
 	processes := d.cfg.SubscriberProcesses
 	if processes <= 0 {
 		processes = 1
 	}
-	if consume := params.SRMaxInFlight * processes; consume > 0 && capacity > consume {
-		capacity = consume
+	if consume := params.SRMaxInFlight * processes; consume > 0 && limit > consume {
+		limit = consume
 	}
+	budget := -1
 	if d.budgets != nil {
 		ops := []string{constants.GatewayOpStop, constants.GatewayOpStart}
 		if groups, _, limited := d.budgets.Budget(ctx, carrierID, ops); limited {
 			for _, remaining := range groups {
-				if remaining < capacity {
-					capacity = remaining
+				if budget < 0 || remaining < budget {
+					budget = remaining
 				}
 			}
 		}
 	}
-	if capacity <= 0 {
+	if limit <= 0 || budget == 0 {
 		return
 	}
 	claimed, expired, err := d.store.ClaimStopResume(ctx, SRClaimInput{
-		CarrierID: carrierID, Lease: d.stopResumeLease(), Capacity: capacity, MinInterval: params.SRMinInterval,
+		CarrierID: carrierID, Lease: d.stopResumeLease(), InflightLimit: limit, Budget: budget, MinInterval: params.SRMinInterval,
 		TokenPrefix: d.instanceID + ":sr:" + strconv.FormatInt(time.Now().UnixNano(), 36),
 	})
 	if err != nil {