OpLogReceptionist should remove Replayers for down nodes

In the periodic tick we should:

```
if let member = self.membership.member(of: peer),
!member.status.isLeaving,
!member.status.isDown {
self.sendAckOps(context, receptionistAddress: peer.address, maybeReceptionistRef: peer)
}
```

as well as just remove the replayer if the member is known to be down already.

We'll never confirm the deliveries and we should not keep them around -> remove the replayer.

Locate OpLogReceptionist and its periodic tick, then read the membership-status handling around the shown sendAckOps condition. Verify the down-member path removes the replayer instead of retaining deliveries that cannot be confirmed; done means down nodes no longer keep replayers and non-down nodes retain the existing acknowledgement behavior.

Written by the indexing model from the issue text.