feat(web-admin): submit stable load/delivery/product ids on plan save.

Co-authored-by: Cursor <cursoragent@cursor.com>

web-admin/src/components/business/pl-plan-form-dialog/index.vue

@@ -1419,6 +1419,7 @@
     return formData.products.map((item) => {
       prepareLineAliasAndBrandForSubmit(item)
       return {
+        ...(item.id ? { id: item.id } : {}),
         productId: item.productId,
         productNo: item.productNo,
         productName: item.productName,
@@ -1779,13 +1780,24 @@
         remark: data.remark || ''
       })
       applyStopsFromPlan(data)
-      loadForm.value.products = loadForm.value.products.map((row) => ({
-        ...row,
-        planProductId: undefined
-      }))
+      // 复制为新计划：不回传源计划段/段产品 id，避免误 upsert
+      loadForm.value = {
+        ...loadForm.value,
+        id: undefined,
+        products: loadForm.value.products.map((row) => ({
+          ...row,
+          id: undefined,
+          planProductId: undefined
+        }))
+      }
       deliveryForms.value = deliveryForms.value.map((row) => ({
         ...row,
-        products: row.products.map((product) => ({ ...product, planProductId: undefined }))
+        id: undefined,
+        products: row.products.map((product) => ({
+          ...product,
+          id: undefined,
+          planProductId: undefined
+        }))
       }))
       loadedTransportStatus.value = 'pending'
       loadedFollowStatus.value = ''