API endpoint to retrieve all defined post statuses and their IDs

I would like an API endpoint to retrieve all defined post statuses, including their names and corresponding IDs.

This would allow me to programmatically manage post states without hardcoding IDs which are unique per workspace nor names.

Currently, the `createPost` API requires the status name, while the `listPosts` API requires status IDs, and there's no documented way to fetch these IDs dynamically.