Assign admin organization

Hookup the frontend to the already made mutations for assigning and revoking and admin of an organization. You can only assign and revoke an admin if you are the creator of the organization. When `assign admin` is clicked it should open a modal and display a list of users to assign and revoke.



Start by locating the frontend's existing organization-admin UI and the already-made assign and revoke mutations. Verify the creator-only condition, then trace the Assign admin interaction to the modal and its user list; done means the frontend can assign and revoke admins through that flow.

Written by the indexing model from the issue text.