projectOptions could be public so external code can use its toProject method to create types.Project

[tigerinus]

Description

I am trying to build a simple code (https://go.dev/play/p/9fcBrgupBpW) in Golang to interact with Docker Compose.
The problem is - after creating a compose project based on the given docker-compose.yml file, no project is listed.
What's expected is something like

$ docker compose ls -a
NAME                STATUS              CONFIG FILES
wp                  created(2)          /home/ubuntu/junk/wp/docker-compose.yml

Inspected the containers created by my code, I noticed that com.docker.compose.project is missing:

            "Labels": {
                "com.docker.compose.config-hash": "350500cdc96e61d71aaecffc207b3b5fd3acbd3e76f29fd278be28265052d7e6",
                "com.docker.compose.container-number": "1",
                "com.docker.compose.depends_on": ""
            }

Looking into compose code, it looks like the label is added as part of toProject(...) method of struct projectOptions, which apparently is not public, so I will have to recreate the same logic in my code to get this to work. Basically I copied the same code from https://github.com/docker/compose/blob/v2/cmd/compose/compose.go#L190-L203

It'd be nice to make projectOptions public so external code can use its toProject method to create types.Project.

[tigerinus]

@ndeloof please see my PR. Thanks!

[ndeloof]

closed by #10103