Hi, you can modify the display of your detailviewdefs by JavaScript custom code by editing
custom/modules/Contacts/metadata/detailviewdefs.php
like this:
array (
'name' => 'full_name',
'label' => 'LBL_NAME',
'customCode' => '
<script type="text/javascript">
if("{$fields.nickname_c.value}" != "")
document.setElementById("full_name").value = "{$fields.salutation.value} {$fields.nickname_c.value}";
</script>',