fix(acceptance): 隔离控制面抖动与租约瞬态故障

线上 P24 验收暴露出高频 kubectl exec 放大 K3s API 压力、门禁查询挤占关键连接池，以及 PostgreSQL 锁超时被误判为租约所有权丢失。

本次合并验收身份查询、在租约有效期内重试瞬态续期错误、修复人工审核残留 attempt，并增加滚动后 etcd 稳定窗口、节点直连指标和双站独立报告。

验证：Go 全量测试、go vet、聚焦 race、gofmt、迁移安全检查、bash -n、ShellCheck、manual release test。

apps/api/internal/store/billing_v2_integration_test.go

@@ -154,6 +154,17 @@ func TestExpiredExecutionLeaseDoesNotReplayAmbiguousUpstreamSubmission(t *testin
 	if review.Status != "failed" || review.BillingStatus != "manual_review" || review.ErrorCode != "upstream_submission_unknown" {
 		t.Fatalf("manual review task=%+v", review)
 	}
+	var attemptStatus string
+	var attemptErrorCode string
+	if err := db.pool.QueryRow(ctx, `
+SELECT status, COALESCE(error_code, '')
+FROM gateway_task_attempts
+WHERE id=$1::uuid`, attemptID).Scan(&attemptStatus, &attemptErrorCode); err != nil {
+		t.Fatal(err)
+	}
+	if attemptStatus != "failed" || attemptErrorCode != "upstream_submission_unknown" {
+		t.Fatalf("manual review attempt status=%s error=%s", attemptStatus, attemptErrorCode)
+	}
 	var outboxStatus string
 	var outboxAction string
 	var reviewReason string

apps/api/internal/store/tasks_runtime.go

@@ -388,6 +388,19 @@ func markTaskExecutionManualReviewTx(
 	hasGatewayUser bool,
 ) error {
 	if _, err := tx.Exec(ctx, `
+UPDATE gateway_task_attempts
+SET status = 'failed',
+    retryable = false,
+    error_code = 'upstream_submission_unknown',
+    error_message = 'upstream submission result is unknown',
+    finished_at = COALESCE(finished_at, now()),
+    upstream_submission_updated_at = now()
+WHERE task_id = $1::uuid
+  AND status = 'running'
+  AND upstream_submission_status IN ('submitting', 'response_received')`, taskID); err != nil {
+		return err
+	}
+	if _, err := tx.Exec(ctx, `
 UPDATE gateway_tasks
 SET status = 'failed',
     billing_status = CASE WHEN $2 THEN 'manual_review' ELSE 'not_required' END,