- WireGuard: refactor to multi-interface 'access classes' model; extract config
generation and helpers into lib/wireguard.py; add per-class up/down endpoints
and API routes; update UI with class management pages and QR code component
- Firewall: fix zone creation with --new-zone before --set-target; skip
masquerade on public zone; add masquerade propagation for nftables backend
so NAT works when internal zones exit via public
- Network: rename sync event subsystem 'network' -> 'networkd'; always stamp
config hash even when deployment fails (fixes pending-changes detection)
- DHCP: add new API endpoint and update frontend page
- State/Sync: update state collectors and sync buses for new subsystems
- Docs: update API and config documentation for new endpoints and schemas
