Well, I created a yml inventory, and it at least syncs now. The project and the inventory source shows a successful sync. However, I wonder if there's a way to display the inventory because using it to run a job from a template says that there is no matching host for a host that I know is in the inventory file:
Identity added: /runner/artifacts/58/ssh_key_data (/runner/artifacts/58/ssh_key_data)
[WARNING]: You are running the development version of Ansible. You should only
run Ansible from "devel" if you are modifying the Ansible engine, or trying out
features under development. This is a rapidly changing source of code and can
become unstable at any point.
[WARNING]: provided hosts list is empty, only localhost is available. Note that
the implicit localhost does not match 'all'
[WARNING]: Could not match supplied host pattern, ignoring:
skipping: no hosts matched
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