fix: support multiple copies printing natively in backend print service

inventory-web/src/views/stock/stocktake/index.vue

@@ -417,8 +417,6 @@ const borrowedQuantities = ref<Record<string, number>>({})
 // ★ 新增: 会话ID
 const currentSessionId = ref<string>('')
 
-// ★ 新增: 差异报告列表
-const varianceList = ref<any[]>([])
 const varianceLoading = ref(false)
 
 const filterType = ref('all')
@@ -830,9 +828,18 @@ const stats = computed(() => {
 })
 
 const varianceList = computed(() => {
-  return allData.value.filter(i =>
-      !i.scanned || (i.scanned && i.qty_actual !== parseFloat(i.qty_stock as any))
-  )
+  return allData.value
+    .filter(i => !i.scanned || (i.scanned && i.qty_actual !== parseFloat(i.qty_stock as any)))
+    .map(i => ({
+      ...i,
+      // 映射字段名以匹配模板
+      stock_name: i.name,
+      stock_spec: i.standard,
+      stock_location: i.location || i.warehouse_loc || '',
+      stock_qty: i.qty_stock,
+      quantity: i.qty_actual,
+      diff_qty: i.qty_actual - parseFloat(i.qty_stock as any)
+    }))
 })
 
 const openInventoryList = () => { showList.value = true }
@@ -872,14 +879,8 @@ const finishStocktake = async () => {
 const openVarianceDialog = async () => {
   varianceLoading.value = true
   showVarianceDialog.value = true
-  try {
-    const res: any = await api.getVarianceReport()
-    varianceList.value = res.list || []
-  } catch (e: any) {
-    ElMessage.error(e?.message || '获取差异报告失败')
-  } finally {
-    varianceLoading.value = false
-  }
+  // varianceList 已通过 computed 自动计算，无需额外 API 调用
+  varianceLoading.value = false
 }
 
 // ★ 新增: 确认平账