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

admin-web/src/api/client.ts

@@ -0,0 +1,75 @@
+const API_BASE = import.meta.env.VITE_API_BASE_URL ?? "/api/v1";
+
+export type User = {
+  id: string;
+  username: string;
+  display_name: string;
+  role: string;
+  is_active: boolean;
+};
+
+export type Device = {
+  id: string;
+  name: string;
+  user_id?: string;
+  platform: string;
+  status: string;
+  assigned_ip?: string;
+};
+
+export type Policy = {
+  id: string;
+  name: string;
+  description: string;
+  priority: number;
+  effect: string;
+  full_tunnel: boolean;
+  is_active: boolean;
+  destinations?: string[];
+};
+
+export type Gateway = {
+  id: string;
+  name: string;
+  endpoint: string;
+  public_key: string;
+  listen_port: number;
+  vpn_cidr: string;
+  dns_servers: string[];
+  is_active: boolean;
+};
+
+export type AuditEvent = {
+  id: string;
+  event_type: string;
+  entity_type: string;
+  status: string;
+  message: string;
+  created_at: string;
+};
+
+async function request<T>(path: string, init?: RequestInit): Promise<T> {
+  const token = localStorage.getItem("nexavpn_admin_token");
+  const response = await fetch(`${API_BASE}${path}`, {
+    ...init,
+    headers: {
+      "Content-Type": "application/json",
+      ...(token ? { Authorization: `Bearer ${token}` } : {}),
+      ...(init?.headers ?? {})
+    }
+  });
+
+  if (!response.ok) {
+    throw new Error(`Request failed: ${response.status}`);
+  }
+
+  return response.json() as Promise<T>;
+}
+
+export const api = {
+  users: () => request<User[]>("/admin/users"),
+  devices: () => request<Device[]>("/admin/devices"),
+  policies: () => request<Policy[]>("/admin/policies"),
+  gateways: () => request<Gateway[]>("/admin/gateways"),
+  audit: () => request<AuditEvent[]>("/admin/audit-logs")
+};