feat(dhcp): DHCPv4-Server via Kea (kea-dhcp4-server) — v1.2.92

Verwalteter DHCPv4-Server analog Unbound/Squid/Chrony.
- Migration 0041: dhcp_settings (singleton, node-lokal), dhcp_subnets, dhcp_reservations.
- internal/kea: Renderer baut Kea-JSON via Go-Struct→Marshal (garantiert valide), managed /etc/edgeguard/kea/kea-dhcp4.conf (Symlink von /etc/kea), Service-Lifecycle an enabled gekoppelt (default AUS, kein rogue DHCP). Interface per NAME (cluster-sicher, kein node-lokaler FK).
- internal/services/dhcp + internal/handlers/dhcp.go: Settings + Subnet/Reservation-CRUD, Validierung (CIDR/IP/MAC/interface exists).
- configgen: Stop/Enable/DisableService. Firewall: AutoFWRule.Iface → udp/67 pro LAN-Interface gescopt (kein WAN). Cluster: subnets/reservations repliziert (hashSpec), dhcp_settings node-lokal (localOnlyTables).
- main.go + render.go + WithAllReloaders Wiring. Packaging: kea-dhcp4-server Dependency, /etc/edgeguard/kea Dir, Symlink, disable-on-install, sudoers (restart/stop/enable/disable).
- UI: DHCP-Seite (Settings + Subnets + Reservierungen pro Subnet), Route/Nav/i18n de/en, HA-Warnung 'nur auf einer Node aktivieren'.
- Tests (guarded EG_FWTEST_DSN): Kea-Renderer gegen DB (valides JSON + Felder), FW-Auto-Rule-Iface inkl. nft -c. Scope v1: DHCPv4.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

packaging/debian/edgeguard-api/DEBIAN/control

@@ -12,7 +12,7 @@ Description: EdgeGuard — native Reverse-Proxy / LB / Forward-Proxy / VPN / Fir
  PG Streaming Replication + provider Floating-IP for HTTP ingress).
  .
  This package ships the management API, scheduler and CLI.
-Depends: postgresql-16 | postgresql-17, haproxy (>= 2.8), squid, wireguard-tools, unbound, chrony, nftables, keepalived, certbot, openssl, sudo, adduser, systemd, ca-certificates, ulogd2, ulogd2-json, iputils-ping, traceroute, dnsutils, curl, netcat-openbsd
+Depends: postgresql-16 | postgresql-17, haproxy (>= 2.8), squid, wireguard-tools, unbound, chrony, kea-dhcp4-server, nftables, keepalived, certbot, openssl, sudo, adduser, systemd, ca-certificates, ulogd2, ulogd2-json, iputils-ping, traceroute, dnsutils, curl, netcat-openbsd
 Recommends: edgeguard-keydb (>= 6.3.4-edgeguard1), apparmor, fail2ban
 Section: admin
 Priority: optional

packaging/debian/edgeguard-api/DEBIAN/postinst

@@ -48,6 +48,7 @@ case "$1" in
         # gespeichert, alles sind Renderer-Outputs.
         for d in /etc/edgeguard /etc/edgeguard/haproxy /etc/edgeguard/squid \
                  /etc/edgeguard/wireguard /etc/edgeguard/unbound \
+                 /etc/edgeguard/kea \
                  /etc/edgeguard/nftables.d; do
             install -d -m 0755 -o "$EG_USER" -g "$EG_USER" "$d"
         done
@@ -118,6 +119,15 @@ edgeguard ALL=(root) NOPASSWD: /usr/bin/systemctl reload chrony.service
 edgeguard ALL=(root) NOPASSWD: /bin/systemctl reload chrony.service
 edgeguard ALL=(root) NOPASSWD: /usr/bin/systemctl restart chrony.service
 edgeguard ALL=(root) NOPASSWD: /bin/systemctl restart chrony.service
+# DHCP (Kea): Service-Lifecycle an dhcp_settings.enabled gekoppelt.
+edgeguard ALL=(root) NOPASSWD: /usr/bin/systemctl restart kea-dhcp4-server.service
+edgeguard ALL=(root) NOPASSWD: /bin/systemctl restart kea-dhcp4-server.service
+edgeguard ALL=(root) NOPASSWD: /usr/bin/systemctl stop kea-dhcp4-server.service
+edgeguard ALL=(root) NOPASSWD: /bin/systemctl stop kea-dhcp4-server.service
+edgeguard ALL=(root) NOPASSWD: /usr/bin/systemctl enable kea-dhcp4-server.service
+edgeguard ALL=(root) NOPASSWD: /bin/systemctl enable kea-dhcp4-server.service
+edgeguard ALL=(root) NOPASSWD: /usr/bin/systemctl disable kea-dhcp4-server.service
+edgeguard ALL=(root) NOPASSWD: /bin/systemctl disable kea-dhcp4-server.service
 edgeguard ALL=(root) NOPASSWD: /usr/bin/apt-get update -qq
 edgeguard ALL=(root) NOPASSWD: /usr/bin/apt-get update
 # Auto-Update-Toggle (Settings → Automatische Updates) schreibt/entfernt
@@ -228,6 +238,19 @@ SUDOERS
         fi
         chown "$EG_USER":"$EG_USER" /etc/chrony/conf.d/edgeguard.conf
         chmod 0644 /etc/chrony/conf.d/edgeguard.conf
+
+        # Kea DHCPv4: managed config unter /etc/edgeguard/kea, vom Distro-
+        # Pfad symlinked (Distro-Original wird gesichert). Der Dienst läuft
+        # NUR, wenn der Operator DHCP aktiviert (Default AUS) — kein
+        # rogue DHCP-Server nach Install. Der Renderer enabled+restartet
+        # kea-dhcp4-server, sobald dhcp_settings.enabled=true gesetzt wird.
+        install -d /etc/kea
+        if [ -f /etc/kea/kea-dhcp4.conf ] && [ ! -L /etc/kea/kea-dhcp4.conf ]; then
+            mv /etc/kea/kea-dhcp4.conf /etc/kea/kea-dhcp4.conf.distro-bak
+        fi
+        ln -sfn /etc/edgeguard/kea/kea-dhcp4.conf /etc/kea/kea-dhcp4.conf
+        systemctl disable --now kea-dhcp4-server.service 2>/dev/null || true
+
         chmod 0440 /etc/sudoers.d/edgeguard
 
         # ── Sysctl-Profil für Edge-Gateway (NAT + HAProxy + Forwarding) ──