Fix Turbo navigation by updating to Turbo-compatible script tag (#1906)

Changed from deprecated 'data-turbolinks-track' to modern 'data-turbo-track'
attribute with 'reload' value. Also explicitly added defer: true for clarity.

This fixes Turbo navigation issues in the dummy app.

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

Co-authored-by: Claude <noreply@anthropic.com>

Author: justin808