Replace Cors::new() with Cors::from(value.settings.cors.clone()) in the
From<Application> for RunnableApplication implementation to use CORS
settings from configuration instead of hardcoded defaults.
Changes:
- Use From<CorsSettings> for Cors trait to build CORS middleware
- Add unit test verifying CORS middleware uses settings
- Maintain correct middleware order: RateLimit → CORS → Data
Ref: T015