fix: usar Storage::url() como base para adjuntos en JS (compatible con producción)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

resources/views/chat/show.blade.php

@@ -86,6 +86,7 @@
 <script>
 const receiverId = {{ $user->id }};
 const authId = {{ auth()->id() }};
+const storageBase = '{{ rtrim(Storage::url(''), '/') }}';
 const chatMessages = document.getElementById('chat-messages');
 
 // scroll al fondo
@@ -118,7 +119,7 @@ document.getElementById('chat-form').addEventListener('submit', function(e) {
 
 function buildAttachmentHtml(msg, isMine) {
     if (!msg.attachment) return '';
-    const url = '/storage/' + msg.attachment;
+    const url = storageBase + '/' + msg.attachment;
     const linkClass = isMine ? 'text-white' : 'text-dark';
     switch (msg.attachment_type) {
         case 'image':