fix: Fix upload_attachment.php AuditLogModel call

- Fix AuditLogModel instantiation with proper $conn parameter
- Fix log() call parameter order (details should be array, not ipAddress)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

api/upload_attachment.php

@@ -171,20 +171,28 @@ try {
     }
 
     // Log the upload
-    $auditLog = new AuditLogModel();
+    $conn = new mysqli(
+        $GLOBALS['config']['DB_HOST'],
+        $GLOBALS['config']['DB_USER'],
+        $GLOBALS['config']['DB_PASS'],
+        $GLOBALS['config']['DB_NAME']
+    );
+    if (!$conn->connect_error) {
+        $auditLog = new AuditLogModel($conn);
         $auditLog->log(
             $_SESSION['user']['user_id'],
             'attachment_upload',
             'ticket_attachments',
-        $attachmentId,
-        null,
-        json_encode([
+            (string)$attachmentId,
+            [
                 'ticket_id' => $ticketId,
                 'filename' => $originalFilename,
                 'size' => $file['size'],
                 'mime_type' => $mimeType
-        ])
+            ]
         );
+        $conn->close();
+    }
 
     ResponseHelper::created([
         'attachment_id' => $attachmentId,