Fix Turbo navigation by updating to Turbo-compatible script tag

When navigating between pages with Turbo, JavaScript wasn't being
re-initialized because the layout was using old Turbolinks data
attributes instead of Turbo attributes.

Changes:
- spec/dummy/app/views/layouts/application.html.erb:
  - Change data-turbolinks-track to data-turbo-track="reload"
  - Add defer: true to ensure proper script loading order with Turbo

This ensures React components properly hydrate on Turbo navigation,
not just on hard refresh.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

Author: justin808

spec/dummy/app/views/layouts/application.html.erb

@@ -10,7 +10,7 @@
   <%= yield :head %>
 
   <!--  NOTE: Must use defer and not async to keep async scripts loading in correct order  -->
-  <%= javascript_pack_tag('client-bundle', 'data-turbolinks-track': true) %>
+  <%= javascript_pack_tag('client-bundle', 'data-turbo-track': 'reload', defer: true) %>
 
   <%= csrf_meta_tags %>
 </head>