Document how to expose SSHServer

Summary

With Implement SSHServer controller (!222 - merged), the Operator V2 reconciles the SSHServer workloads but does not expose them via NodePort/LoadBalancer/Ingress. We need to document how users can configure their own Ingress or NodePort or LoadBalancer.

Success criteria

• Document how to expose the SSHServer via NGINX
• Document how to expose the SSHServer via traefik
• Document alternative ways to expose the SSHServer