修复同步状态接口返回格式导致前端崩溃

backend/internal/handlers/stock.go

@@ -139,11 +139,7 @@ func (h *StockHandler) SyncStatus(c *gin.Context) {
 		c.JSON(http.StatusInternalServerError, gin.H{"success": false, "error": "查询同步状态失败"})
 		return
 	}
-	if job == nil {
+	c.JSON(http.StatusOK, job)
-		c.JSON(http.StatusOK, gin.H{"success": true, "data": nil})
-		return
-	}
-	c.JSON(http.StatusOK, gin.H{"success": true, "data": job})
 }
 
 // TriggerSync 手动触发同步（管理员）。

frontend/src/components/StockOverview.tsx

@@ -265,6 +265,7 @@ function StockList({
 }
 
 function formatSyncStatus(job: SyncJob): string {
+  if (!job || !job.id) return '状态未知'
   if (job.status === 'running') return '同步中…'
   const ts = job.finished_at || job.started_at
   let timeStr = '时间未知'