pixi global install fails when package name contains dot

[janjagusch]

Checks

• I have checked that this issue has not already been reported.

• I have confirmed this bug exists on the latest version of pixi, using pixi --version.

Reproducible example

This used to work in v0.32.1:

docker run ghcr.io/prefix-dev/pixi:0.32.1 pixi global install ruamel.yaml
No executable entrypoint found in package ruamel.yaml, are you sure it exists?
Installed package ruamel.yaml 0.18.6 py313h31d5739_1 from conda-forge

But broke in v0.33.0:

docker run ghcr.io/prefix-dev/pixi:0.33.0 pixi global install ruamel.yaml
Status: Downloaded newer image for ghcr.io/prefix-dev/pixi:0.33.0
  × Failed to parse environment name 'ruamel.yaml', please use only lowercase
  │ letters, numbers, dashes and underscores

And has been broken since:

docker run ghcr.io/prefix-dev/pixi:0.39.0 pixi global install ruamel.yaml
  × Failed to parse environment name 'ruamel.yaml', please use only lowercase
  │ letters, numbers, dashes and underscores

Issue description

Running pixi global install <package_name>, where the package name contains a dot (e.g., ruamel.yaml) yields an unexpected error.

Expected behavior

I expect to be able to install such packages globally.