refactor: standardize port to 1999 across all files

- Updated default port from 8080 to 1999 in config, Docker, and documentation files
- Modified example URLs and test commands to use new port
- Ensured consistent port references in environment configs and deployment examples
- Updated health check endpoints in Docker and testing scripts

The port change aligns with LIV Golf port allocation standards for staging environments (5000-9999 range).

.env.example

@@ -2,7 +2,7 @@
 # Copy this file to .env and customize as needed
 
 # Server Configuration
-PORT=8080
+PORT=1999
 HOST=localhost
 GO_ENV=development