Dynamic fetching of allowed parent work item types based on namespace and plan

Summary

With !201980 (merged), we introduced the Parent filter, but it currently relies on hardcoded allowed parent types. This issue targets to

• Remove the hardcoded parent types.
• Add a query to dynamically fetch supported parent types based on the namespace and its plan.
• Ensure the query validates whether the work item type is enabled.
  • For example, if the group/project is on the Free tier, it should exclude paid features like Epic and Objective from the results.

This will ensure that parent types are accurately determined based on the namespace context and subscription level.