revert(ldap): remove CTL-specific AD connection prefill

The prior quick task (260707-csw) pre-filled the LDAP connection form
with one customer's specific Active Directory values (balios.ctl.local,
dc=ctl,dc=local) and a matching bind-DN hint. User clarified this was
never wanted -- Tessera is a generic multi-tenant product, and baking
one customer's infrastructure into the shared admin UI is wrong,
especially since a `dcdown -v` reinstall surfaced it unexpectedly as
seemingly-baked-in defaults on a fresh system.

Reverted to blank fields with generic example placeholders
(ldap.example.com / dc=example,dc=com / cn=admin,dc=example,dc=com),
matching the form's state before that change. Removed the now-unused
bindDnHint i18n key.

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

apps/web/src/app/(portal)/admin/ldap/page.tsx

@@ -61,17 +61,12 @@ export default function AdminLdapPage() {
   const [syncing, setSyncing] = useState(false);
 
   // Form state for connection settings.
-  // Defaults are pre-filled with the known-good CTL Active Directory
-  // connection values (sourced from the working XWiki LDAP config) so a
-  // brand-new setup only needs the service-account password. fetchConfig()
-  // below overwrites these with the real saved values whenever a config
-  // already exists.
   const [formData, setFormData] = useState({
-    serverUrl: 'ldap://balios.ctl.local:3268',
-    baseDn: 'dc=ctl,dc=local',
+    serverUrl: '',
+    baseDn: '',
     bindDn: '',
     bindPassword: '',
-    searchFilter: '(&(objectClass=user)(objectCategory=person))',
+    searchFilter: '(objectClass=person)',
     syncIntervalMin: 60,
     isActive: true,
   });
@@ -342,11 +337,10 @@ export default function AdminLdapPage() {
                 type="text"
                 value={formData.bindDn}
                 onChange={(e) => setFormData({ ...formData, bindDn: e.target.value })}
-                placeholder="ctl\serviceaccount"
+                placeholder="cn=admin,dc=example,dc=com"
                 className="flex h-10 w-full rounded-md border border-input bg-background px-3 py-2 text-sm"
                 required
               />
-              <p className="text-xs text-muted-foreground">{t('bindDnHint')}</p>
             </div>
             <div className="space-y-2">
               <label className="text-sm font-medium text-foreground">