Add command to list available packages from package_manifest.yaml

[ogajduse]

Problem

Currently, there is no CLI command in obal that allows users to see which packages are available for operations as defined in package_manifest.yaml. This makes it harder for users to discover what packages are supported by their current configuration.

Proposal

Implement a command, e.g., obal list or obal list-packages, that prints the list of available packages found in package_manifest.yaml. This command should:

• Parse package_manifest.yaml.
• Output a list of all packages that obal can operate on, in a clear and human-readable format.

[ekohl]

In tab completion it doesn't know the distinction between packages and groups. I'm not sure we even can do that at all.

[ogajduse]

I'll put this one here:

ansible-inventory -i package_manifest.yaml --list | python3 -c "import sys, json; data=json.load(sys.stdin);hosts=[h for h in data.get('_meta', {}).get('hostvars', {}).keys() if not h.endswith('-copr')]; print('\n'.join(sorted(hosts)))"

This one is close, but still imperfect, as it lists repoclosures.