[Request]: explicitly proxy to external tool for compose

### Feature or enhancement request details

Basing on https://github.com/apple/container/pull/2123#issuecomment-5457807598 it was revealed that this project has no intent to implement `docker compose` feature (unfortunately this is the only place i found that, without any replies in discussions)

Then can it be done explicit and supporting the syntax of other tools, so the user could call `container compose` the same way as `podman compose`, `docker compose`, etc.

some env var setting like `APPLE_CONTAINER_COMPOSE_TOOL` that will allow to set it would be just enough, that will just proxy this feature.

Also it bring a boundary for this project scope giving the signal to other devs that this piece of complexity will not be implemented, closing https://github.com/apple/container/discussions/194

### Code of Conduct

- [x] I agree to follow this project's Code of Conduct

Start by locating the CLI entry point that dispatches container subcommands and review how external tools or environment variables are handled. Add an explicit container compose path configurable through APPLE_CONTAINER_COMPOSE_TOOL, preserving the syntax expected by tools such as podman compose and docker compose; done means the command proxies to the selected tool and the behavior is covered by relevant CLI tests.

Written by the indexing model from the issue text.