Function project_ops 

pub fn project_ops(ops: Vec<NormalizedOp>, proj: &ProjMap) -> Vec<NormalizedOp>

Project every op’s rows to the per-table column set (§5.2). A no-op when proj is empty. pub (not pub(crate)): rindle-replica’s Drain applies the same projection on its own fanout path, and the room’s downstream publisher will too.