fix(canvas): 文本生成 - 修复分镜超时并贯通 Agent 与创作页流式返回

backend/internal/handler/routes.go

@@ -234,6 +234,10 @@ func streamTaskTextEvents(c *gin.Context, svc *service.Service, userID string, t
 		return
 	}
 	c.Writer.Flush()
+	lastStatus := replay.Status
+	lastStage := replay.Stage
+	lastProgress := replay.Progress
+	writeTaskTextSSE(c, "progress", 0, map[string]any{"status": replay.Status, "stage": replay.Stage, "progress": replay.Progress})
 
 	pollTicker := time.NewTicker(750 * time.Millisecond)
 	heartbeatTicker := time.NewTicker(15 * time.Second)
@@ -263,6 +267,10 @@ func streamTaskTextEvents(c *gin.Context, svc *service.Service, userID string, t
 			writeTaskTextSSE(c, "error", 0, map[string]string{"message": "任务文本流不可用"})
 			return
 		}
+		if next.Status != lastStatus || next.Stage != lastStage || next.Progress != lastProgress {
+			writeTaskTextSSE(c, "progress", 0, map[string]any{"status": next.Status, "stage": next.Stage, "progress": next.Progress})
+			lastStatus, lastStage, lastProgress = next.Status, next.Stage, next.Progress
+		}
 		replay = next
 	}
 }