feat(network): VLAN/bridge/bond interface provisioner + IP-address apply

Fügt zwei neue systemd-oneshot-Services hinzu:
- edgeguard-interfaces.service: erstellt VLAN/bridge/bond-Interfaces
  (ip link add/del) wenn der Operator sie über die GUI anlegt/entfernt.
  Ethernet + WireGuard bleiben OS-managed.
- edgeguard-ipaddresses.service: bindet/entfernt IP-Adressen (ip addr
  add/del) nach jeder GUI-Mutation; läuft jetzt After=edgeguard-interfaces
  damit Interfaces immer vor den Adressen existieren.

Beide Services triggern per applyAsync() in den zugehörigen Handlern
(networks.go → Interfaces, ipaddresses.go → Adressen). Diff-Ansatz
über *-applied.conf verhindert dass manuell gebundene Adressen/
Interfaces angefasst werden.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

internal/handlers/ipaddresses.go

@@ -1,7 +1,9 @@
 package handlers
 
 import (
+	"context"
 	"errors"
+	"log/slog"
 	"strconv"
 
 	"github.com/gin-gonic/gin"
@@ -13,13 +15,27 @@ import (
 )
 
 type IPAddressesHandler struct {
-	Repo   *ipaddresses.Repo
-	Audit  *audit.Repo
-	NodeID string
+	Repo      *ipaddresses.Repo
+	Generator *ipaddresses.Generator
+	Audit     *audit.Repo
+	NodeID    string
 }
 
 func NewIPAddressesHandler(repo *ipaddresses.Repo, a *audit.Repo, nodeID string) *IPAddressesHandler {
-	return &IPAddressesHandler{Repo: repo, Audit: a, NodeID: nodeID}
+	return &IPAddressesHandler{
+		Repo:      repo,
+		Generator: ipaddresses.NewGenerator(repo),
+		Audit:     a,
+		NodeID:    nodeID,
+	}
+}
+
+func (h *IPAddressesHandler) applyAsync(ctx context.Context) {
+	go func() {
+		if err := h.Generator.Render(ctx); err != nil {
+			slog.Warn("ip-addresses: apply failed", "error", err)
+		}
+	}()
 }
 
 func (h *IPAddressesHandler) Register(rg *gin.RouterGroup) {
@@ -70,6 +86,7 @@ func (h *IPAddressesHandler) Create(c *gin.Context) {
 	}
 	_ = h.Audit.Log(c.Request.Context(), actorOf(c), "ip_address.create",
 		req.Address, out, h.NodeID)
+	h.applyAsync(c.Request.Context())
 	response.Created(c, out)
 }
 
@@ -94,6 +111,7 @@ func (h *IPAddressesHandler) Update(c *gin.Context) {
 	}
 	_ = h.Audit.Log(c.Request.Context(), actorOf(c), "ip_address.update",
 		out.Address, out, h.NodeID)
+	h.applyAsync(c.Request.Context())
 	response.OK(c, out)
 }
 
@@ -112,5 +130,6 @@ func (h *IPAddressesHandler) Delete(c *gin.Context) {
 	}
 	_ = h.Audit.Log(c.Request.Context(), actorOf(c), "ip_address.delete",
 		strconv.FormatInt(id, 10), gin.H{"id": id}, h.NodeID)
+	h.applyAsync(c.Request.Context())
 	response.NoContent(c)
 }