fix(nodes): clean up orphaned client_inbounds on node inbound removal

When a remote node disconnects or one of its inbounds vanishes from the
traffic snapshot, setRemoteTrafficLocked deleted the central inbound row
but left the client_inbounds join rows behind. Affected clients ended up
linked to hundreds of phantom inbounds, and editing one then failed with
"record not found" / "Load Old Data Error" because Update aborted on the
first GetInbound miss.

- Detach client_inbounds rows when deleting a vanished node inbound
- Prune stale links during client Update instead of aborting the save
- Drop orphaned client_inbounds rows on startup to heal existing DBs

Closes #4636

web/service/inbound.go

@@ -1432,6 +1432,9 @@ func (s *InboundService) setRemoteTrafficLocked(nodeID int, snap *runtime.Traffi
 			Delete(&xray.ClientTraffic{}).Error; err != nil {
 			return false, err
 		}
+		if err := s.clientService.DetachInbound(tx, c.Id); err != nil {
+			return false, err
+		}
 		if err := tx.Where("id = ?", c.Id).
 			Delete(&model.Inbound{}).Error; err != nil {
 			return false, err