interface TreeData id "tree:data" revision "tree:data@1" {
  operation reparent id "tree:reparent" : optional<interface-ref<TreeData>> -> unit {
    call id "tree:reparent:call" execution transaction targets [browser, server];
  }
  queryable relation parent id "tree:parent" : optional-one interface TreeData {
    resolve id "tree:parent:resolve" execution snapshot targets [browser, server];
  }
  queryable relation children id "tree:children" : many interface TreeData {
    resolve id "tree:children:resolve" execution snapshot targets [browser, server];
  }
}