Add "new" Command

[adrum]

This command allows you to create a new project using cpx. We have a couple different repos for bootstrapping projects, so this makes it pretty easy to quickly scaffold a new project from them.

• cpx new laravel/laravel project or cpx new laravel/laravel:^11.0 project

• cpx new craftcms/craft project

• cpx new symfony/skeleton project

[imliam]

What is the advantage of this command over just using composer create-project directly?

[adrum]

@imliam My own personal use case isn't fully realized until #12 would be merged. I have some private git repos thats aren't packages that I use for project templates. It can be a bit wordy:

composer create-project package/name --stability=dev --repository='{"type":"git", "url":"https://example.com/group/repo", "options": {"symlink": false}}' my-app.

I thought it made sense to split up #11 and #12, even though my ultimate goal is using them together.

Also, cpx new feels like a natural short command to be included, even though it does proxy to composer create-project under the hood.