Once MVCC range tombstones are implemented in #70412, and used in DeleteRange in #70415, they should be emitted across rangefeeds. These will be recorded as a new MVCCDeleteRangeOpType logical op type, and emitted as a new RangeFeedDeleteRange rangefeed event. These will be emitted whenever DeleteRange is called with the UseExperimentalRangeTombstone parameter, and also during catchup scans, but not during initial scans (which never emit tombstones).

Epic CRDB-2624

Jira issue: CRDB-16401