SOLR-18140: Try to bandaid the DELETENODE docs for a broken API (#4170)

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

Author: epugh

solr/solr-ref-guide/modules/deployment-guide/pages/cluster-node-management.adoc

@@ -667,7 +667,7 @@ Examining the clusterstate after issuing this call should show exactly one repli
 == Migrate Replicas
 
 Migrate all replicas off of a given set of source nodes.
-+
+
 If more than one node is used as a targetNode (either explicitly, or by default), then the configured
 xref:configuration-guide:replica-placement-plugins.adoc[Replica Placement Plugin] will be used to determine
 which targetNode should be used for each migrated replica.
@@ -862,7 +862,12 @@ So don't perform other collection operations in this period.
 == DELETENODE: Delete Replicas in a Node
 
 Deletes all replicas of all collections in that node.
-Please note that the node itself will remain as a live node after this operation.
+Please note that the node itself will remain as a live node after this operation if it is currently functioning.
+
+[TIP]
+====
+If the node is currently down and you aren't bringing it back, then this command removes that node's replica entries from the cluster state (ZooKeeper), cleaning up references to its replicas. It does not change the node's liveness in `/live_nodes`, and the node may still rejoin the cluster if it is started again later.
+====
 
 [tabs#deletenode-request]
 ======