Enhance Event admin UI and fix translations

- Remove default_locale and primary_join_token columns from event list
- Add read-only join link field to event edit form
- Add missing translations for used/remaining photos and join link
- Fix array-to-string conversion error in join link modal

resources/lang/en/admin.php

@@ -363,16 +363,16 @@ return [
             'date' => 'Event Date',
             'type' => 'Event Type',
             'default_locale' => 'Default Locale',
-            'is_active' => 'Is Active',
             'settings' => 'Settings',
+            'join_link' => 'Invitation Link',
         ],
         'table' => [
             'tenant' => 'Tenant',
             'join' => 'Join',
             'join_tokens_total' => 'Invitations: :count',
-            'join_tokens_missing' => 'No invitations created yet',
             'package' => 'Package',
-        ],
+            'used_photos' => 'Used Photos',
+            'remaining_photos' => 'Remaining',        ],
         'relation_managers' => [
             'event_packages' => [
                 'title' => 'Event Packages',