feat: [datafetcher] Add the datafetcher implementation
needs https://forge.extranet.logilab.fr/open-source/LDBrowser/libview/-/merge_requests/5 By the way, add the node id to the simple render signature.
needs https://forge.extranet.logilab.fr/open-source/LDBrowser/libview/-/merge_requests/5 By the way, add the node id to the simple render signature.