Issue Summary

When the Assignable User permission is granted via a group picker custom field, an assignee can't be set through bulk edit even if they are a valid assignee for all included work items.

The bulk edit checks permission for the project, and doesn't evaluate the individual work items.

Steps to Reproduce

1. Update the project permission scheme so that Assignable user is only granted to a group picker custom field
2. Set the group picker to a valid group on at least one work item
3. Start a bulk edit of those those items, etiher:
   • Select the item in the List or Backlog view and go to Edit fields in the bulk edit modal
   • Search for the items and go to "..." > Buk change work items
4. Try to select another user in that group as the new assignee (not yourself)

Expected Results

You should be able to choose from a list of users who are members of the group and valid assignees for the selected work items

Actual Results

The only assignee options shown are 'Unassigned' and sometimes your own account.

Workaround

• Set the assignee on each work item individually
• Use an automation rule (example attached for reference)