fix(tasks): 任务队列 - 执行前重查排队任务的自定义渠道开关 (#682)

Co-authored-by: ddcat666 <26564566+ddcat666@users.noreply.github.com>

backend/internal/app/task_worker.go

@@ -191,6 +191,34 @@ func (w *taskWorkerCoordinator) processClaimedTask(task *model.Task, globalSlot
 		return s.finishTaskMediaRecovery(task, result, recoveryErr)
 	}
 
+	// Creation and manual retry admission can precede execution by a long time.
+	// Re-read the feature policy before preparing or dispatching a model route.
+	decryptedInput, err := s.decryptTaskInputJSON(task.InputJSON)
+	if err != nil {
+		return err
+	}
+	var admissionInput map[string]any
+	if err := json.Unmarshal([]byte(decryptedInput), &admissionInput); err != nil {
+		return err
+	}
+	if err := s.requireCustomChannelsForTaskInput(admissionInput); err != nil {
+		// A reclaimed task may already have submitted upstream. Keep the existing
+		// review path for that evidence; only an unsent reservation is refundable.
+		attempts, readErr := s.repo.RouteAttempts(task.ID, task.RouteRun)
+		uncertain := readErr != nil || task.ProviderRequestID != "" || s.taskBilling().BillingFailureRequiresReview(task.BillingOrderID, task.ID, err)
+		for _, attempt := range attempts {
+			if attempt.DispatchState == "accepted" || attempt.DispatchState == "submission_unknown" {
+				uncertain = true
+			}
+		}
+		// Legacy tasks without an explicit new retry run retain their conservative
+		// submission handling, as in createDirectTaskAttempt.
+		if len(attempts) == 0 && task.RouteRun <= 1 && task.Attempts > 1 {
+			uncertain = true
+		}
+		return terminal.markPreparationFailure(task, "渠道不可用", errors.Join(err, readErr), uncertain, "自定义渠道已关闭，上游请求未发出")
+	}
+
 	s.markAgentMemoryCompactRunning(*task)
 	task.Stage = "调用生成模型"
 	task.Progress = 35