- EffectiveConfigFieldRef as value type; PendingDnsmasqChange/PendingOptionChange/PendingManagedHostsChange
- Multi-file save plan (DnsmasqSaveWritePlan, DnsmasqManagedBackup) and backup/restore in save flow
- Hosts integrated into effective-config save; Hosts.razor uses shared save modal
- IEffectiveConfigDescriptorProvider + IEffectiveConfigFieldBuilder (DI); descriptors from EffectiveConfigSections
- IEffectiveConfigPageEditor, shared descriptor resolution; addn-hosts/dhcp-host descriptor fix
- DnsmasqConfText, IEffectiveConfigDirectiveSerializer; DnsmasqConfigService uses serializer for writes
- IStructuredOptionValueHandler/Registry, DhcpHostOptionValueHandler; Dhcp.razor index-based DeleteRow fix
- SaveService: roll back partial writes on failure; SaveModal: WriteFailed shows backups and Restore button
