chore: initial project scaffold with admin web, backend, desktop client, and deployment setup

Add monorepo structure for NexaVPN WireGuard control plane including:
- .gitignore for node_modules, build artifacts, and environment files
- README with project overview, monorepo layout, and quick start guide
- Admin web UI with React, Vite, TypeScript, and nginx reverse proxy
- API client with type definitions for users, devices, policies, gateways, and audit logs
- Admin pages for dashboard, users, devices, policies, g

backend/internal/policy/handler.go

@@ -0,0 +1,62 @@
+package policy
+
+import (
+	"encoding/json"
+	"net/http"
+
+	"github.com/nexavpn/nexavpn/backend/internal/apiutil"
+	"github.com/nexavpn/nexavpn/backend/internal/audit"
+	"github.com/nexavpn/nexavpn/backend/internal/httpserver"
+)
+
+type Handler struct {
+	service *Service
+	audit   *audit.Service
+}
+
+func NewHandler(service *Service, auditService *audit.Service) *Handler {
+	return &Handler{service: service, audit: auditService}
+}
+
+func (h *Handler) List(w http.ResponseWriter, r *http.Request) {
+	items, err := h.service.List(r.Context())
+	if err != nil {
+		apiutil.Error(w, http.StatusInternalServerError, "policies_list_failed", "unable to list policies")
+		return
+	}
+
+	apiutil.JSON(w, http.StatusOK, items)
+}
+
+func (h *Handler) Create(w http.ResponseWriter, r *http.Request) {
+	var input CreateRequest
+	if err := json.NewDecoder(r.Body).Decode(&input); err != nil {
+		apiutil.Error(w, http.StatusBadRequest, "invalid_json", "invalid request body")
+		return
+	}
+
+	claims, ok := httpserver.ClaimsFromContext(r.Context())
+	if !ok {
+		apiutil.Error(w, http.StatusUnauthorized, "unauthorized", "missing auth claims")
+		return
+	}
+
+	item, err := h.service.Create(r.Context(), claims.UserID, input)
+	if err != nil {
+		apiutil.Error(w, http.StatusInternalServerError, "policy_create_failed", "unable to create policy")
+		return
+	}
+
+	_ = h.audit.Record(r.Context(), audit.Entry{
+		ActorUserID: &claims.UserID,
+		EntityType:  "policy",
+		EntityID:    &item.ID,
+		EventType:   "admin.policy.created",
+		Status:      "success",
+		Message:     "admin created policy",
+		Metadata: map[string]any{
+			"name": item.Name,
+		},
+	})
+	apiutil.JSON(w, http.StatusCreated, item)
+}