Prevent Accidental Deletion of Long-Term Templates

When users attempt to delete a long-term template, a clear warning should be displayed to inform them that this action is irreversible. The current warning 'The last long-term template cannot be deleted' can be improved by using a more concise and specific message. Consider replacing it with something like 'Deleting this long-term template is permanent.' This helps users understand the consequences of their action and prevents accidental deletions.