Enhance deployment scripts and monitoring configuration (#76)

- Updated healthcheck command in docker-compose.monitoring.yml to use --spider for better validation.
- Modified NGINX health endpoint to always return JSON content type.
- Improved debugging in deploy-bluegreen.sh by enabling xtrace based on DEBUG environment variable.
- Enhanced logging in deploy-bluegreen.sh to include deploy ID in log messages.
- Added error handling and logging for command executions in deploy-bluegreen.sh.
- Refactored health check logic to simplify and improve reliability.
- Implemented phase timing helpers for better tracking of deployment phases.
- Added GitHub Actions summary reporting at the end of the deployment process.
- Cleaned up redundant code and improved readability throughout the deployment script.

Author: rajashish147