Support fullPath in Work Item Bulk Edit Mutation to Replace parentId

Currently, the work item bulk editing mutation relies on parentId, which requires an extra query to determine whether the ID refers to a group or a project. This adds complexity and an additional API call.

We propose adding support for fullPath instead of parentId in the mutation. This allows the backend to directly resolve the target group or project, streamlining the mutation process and eliminating the need for a separate query.