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/wireguard/types.go

@@ -0,0 +1,18 @@
+package wireguard
+
+type Peer struct {
+	DeviceID            string   `json:"device_id"`
+	PublicKey           string   `json:"public_key"`
+	AssignedIP          string   `json:"assigned_ip"`
+	AllowedDestinations []string `json:"allowed_destinations"`
+}
+
+type GatewayBundle struct {
+	GatewayID string `json:"gateway_id"`
+	Revision  int    `json:"revision"`
+	Interface struct {
+		Address    string `json:"address"`
+		ListenPort int    `json:"listen_port"`
+	} `json:"interface"`
+	Peers []Peer `json:"peers"`
+}