[repo] more efficient eid cache operations handling based on set_operation; refactor * split CleanupEidTypeCache operation into one operation for deleted eids and another for added eids, and put them in cw.server.hook * for consistency, move fti unindexing handling from the repository to the system source * handling of deleted eids is done in plan execution (ssplanner), no needs to redo it in *delete_info -> no more need for _prepare_delete_info method, killed