Delete and DeleteByEmail removed client_traffics, global-traffic, and
inbound_client_ips rows but never the per-node baseline rows in
node_client_traffics, so every deleted client left orphaned baselines
behind for each registered node. The shared DelClientStat and
delClientStatsByEmails helpers already clean that table; mirror the
same cleanup in both row-cleanup paths so the record-only and
record-less delete flows stop leaking baselines.
Closes#5841
MHSanaei