fix(media): 媒体恢复 - 保留音频多结果并兼容单数响应

backend/internal/app/task_media_recovery.go

@@ -110,9 +110,6 @@ func recoverProtocolMedia(ctx context.Context, config providerConfig, mode strin
 	if len(references) == 0 || len(references) > 32 {
 		return nil, true, &mediaRecoveryError{stage: "checkpoint", cause: errors.New("生成结果数量超过恢复限制")}
 	}
-	if mode != "image" {
-		references = references[:1]
-	}
 	if task.MediaRecoveryJSON != "" {
 		result, err := s.resumeTaskMedia(ctx, task)
 		return result, true, err
@@ -246,6 +243,10 @@ func (s *Service) materializeTaskMedia(ctx context.Context, task *model.Task, co
 	result = map[string]interface{}{"mode": checkpoint.Mode}
 	if checkpoint.Mode == "image" {
 		result["images"] = items
+	} else if checkpoint.Mode == "audio" {
+		result["audios"] = items
+		// Keep the legacy singular field for clients that render one audio result.
+		result["audio"] = items[0]
 	} else {
 		result[checkpoint.Mode] = items[0]
 	}

backend/internal/app/task_media_recovery_test.go

@@ -409,3 +409,37 @@ func TestMediaRecoveryExpiredLeaseAndStagingLimits(t *testing.T) {
 		t.Fatal("staging budget exceeded")
 	}
 }
+
+func TestMediaRecoveryAudioKeepsAllReturnedResults(t *testing.T) {
+	t.Setenv("CANVAS_ALLOWED_PRIVATE_UPSTREAM_HOSTS", "127.0.0.1")
+	s, db := newMediaRecoveryTestService(t)
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", "audio/mpeg")
+		_, _ = w.Write([]byte("audio-result"))
+	}))
+	defer server.Close()
+	expires := time.Now().Add(time.Hour)
+	input, err := json.Marshal(canvasGenerationInput{Mode: "audio", Config: providerConfig{BaseURL: server.URL}, Prompt: "test"})
+	if err != nil {
+		t.Fatal(err)
+	}
+	task := &model.Task{ID: newID(), UserID: "media-user", Type: "canvas_audio", Status: model.TaskStatusRunning, InputJSON: string(input), LeaseOwner: "worker-a", LeaseExpiresAt: &expires, RouteRun: 1, CreatedAt: time.Now()}
+	if err := db.Create(task).Error; err != nil {
+		t.Fatal(err)
+	}
+	ctx := context.WithValue(withProviderAnalytics(context.Background(), s, *task), mediaExecutionTaskKey{}, *task)
+	result, handled, recoveryErr := recoverProtocolMedia(ctx, providerConfig{BaseURL: server.URL}, "audio", []protocol.MediaReference{
+		{URL: server.URL + "/voice.wav", MIMEType: "audio/mpeg"},
+		{URL: server.URL + "/emotion.wav", MIMEType: "audio/mpeg"},
+	})
+	if !handled || recoveryErr != nil {
+		t.Fatalf("handled=%v err=%v", handled, recoveryErr)
+	}
+	audios, ok := result["audios"].([]interface{})
+	if !ok || len(audios) != 2 {
+		t.Fatalf("audios=%#v result=%#v", result["audios"], result)
+	}
+	if _, ok := result["audio"]; !ok {
+		t.Fatal("legacy singular audio result missing")
+	}
+}