Add new setting PURCHASEORDER_AUTO_COMPLETE (#6245)

* Add new setting PURCHASEORDER_AUTO_COMPLETE

- Controls whether purchase orders are automatically closed
- Default to True

* Tweak setting component

src/frontend/src/components/settings/SettingItem.tsx

@@ -172,8 +172,8 @@ export function SettingItem({
 
   return (
     <Paper style={style}>
-      <Group position="apart" p="10">
-        <Stack spacing="2">
+      <Group position="apart" p="3">
+        <Stack spacing="2" p="4px">
           <Text>{setting.name}</Text>
           <Text size="xs">{setting.description}</Text>
         </Stack>

src/frontend/src/pages/Index/Settings/SystemSettings.tsx

@@ -238,7 +238,8 @@ export default function SystemSettings() {
           <GlobalSettingList
             keys={[
               'PURCHASEORDER_REFERENCE_PATTERN',
-              'PURCHASEORDER_EDIT_COMPLETED_ORDERS'
+              'PURCHASEORDER_EDIT_COMPLETED_ORDERS',
+              'PURCHASEORDER_AUTO_COMPLETE'
             ]}
           />
         )