Fix that the "all" forum aggregation view would not always include some link-forum nodes when "Proxy Link Forums" add-on is installed
Massively simplify User::isNodeAggregated and is now a wrapper on Node::isAggregated, now only functions in the XF\Pub\Controller\Forum\actionForum context. It now correctly detects and handlings proxy link-forum add-on which requires the context to correctly mark child-forums as aggregated without iterating the node-tree for every isNodeAggregated call