fix: too long file names

lib/widgets/event_content/message_download_content.dart

@@ -30,12 +30,14 @@ class MessageDownloadContent extends StatelessWidget {
               children: [
                 Icon(Icons.download_outlined),
                 SizedBox(width: 8),
-                Text(
+                Expanded(
+                  child: Text(
                     filename,
                     overflow: TextOverflow.fade,
                     softWrap: false,
                     maxLines: 1,
                   ),
+                ),
               ],
             ),
           ),