Fix sshPublicKey ObjectClassViolationError and blank OAuth parent dropdown

- User.update/addSSHkey now ensure the ldapPublicKey objectClass is present
  before writing sshPublicKey, so accounts predating that objectClass
  (e.g. the bootstrap admin) no longer 500 on PUT /api/user/:uid.
- populateHostDropdown in directory.ejs was missing an `oauth` branch,
  leaving the parent-Service picker blank when adding an OAuth Integration.
- Bump to 1.5.1.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

nodejs/views/directory.ejs

@@ -572,6 +572,8 @@
         $target.append($('<option>').val(r.id).text(r.name + ' (' + r.slug + ')'));
       } else if (kind === 'service' && (r.kind === 'host' || r.kind === 'service')) {
         $target.append($('<option>').val(r.id).text(r.name + ' (' + r.slug + ')'));
+      } else if (kind === 'oauth' && r.kind === 'service') {
+        $target.append($('<option>').val(r.id).text(r.name + ' (' + r.slug + ')'));
       }
     });
     if (selectedId) $target.val(selectedId);