Fix GlobalSearch crash when ParticipantStatus enum is cast to string

ParticipantStatus is a backed enum — concatenating it directly throws.
Use ->value to get the string value.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

app/Livewire/GlobalSearch.php

@@ -51,7 +51,7 @@ public function search(): void
             $results[] = [
                 'type' => 'participant',
                 'label' => $p->person?->name_ar ?? $p->person?->name ?? $p->participant_number,
-                'subtitle' => $p->participant_number . ' — ' . ($p->status ?? ''),
+                'subtitle' => $p->participant_number . ' — ' . ($p->status?->value ?? ''),
                 'url' => route('participants.show', $p),
             ];
         }