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

desktop-client/src/styles.css

@@ -0,0 +1,111 @@
+:root {
+  font-family: "Segoe UI", "SF Pro Text", sans-serif;
+  color: #f5f7fb;
+  background:
+    radial-gradient(circle at top, rgba(79, 208, 164, 0.18), transparent 25%),
+    linear-gradient(180deg, #08111f 0%, #0d1727 100%);
+}
+
+* {
+  box-sizing: border-box;
+}
+
+body {
+  margin: 0;
+}
+
+.client-shell {
+  min-height: 100vh;
+  display: grid;
+  place-items: center;
+  gap: 24px;
+  padding: 32px 20px;
+}
+
+.hero,
+.panel {
+  width: min(560px, 100%);
+}
+
+.hero {
+  text-align: center;
+}
+
+.eyebrow {
+  color: #74e0b8;
+  letter-spacing: 0.18em;
+  text-transform: uppercase;
+  font-size: 0.78rem;
+}
+
+.lede {
+  color: #a9b8d3;
+}
+
+.panel {
+  padding: 24px;
+  border-radius: 24px;
+  background: rgba(12, 22, 38, 0.84);
+  border: 1px solid rgba(167, 185, 219, 0.14);
+  box-shadow: 0 24px 60px rgba(2, 8, 18, 0.36);
+  backdrop-filter: blur(16px);
+}
+
+form {
+  display: grid;
+  gap: 16px;
+}
+
+label {
+  display: grid;
+  gap: 8px;
+  color: #c2cfe5;
+}
+
+input {
+  border: 1px solid rgba(167, 185, 219, 0.16);
+  background: rgba(7, 14, 27, 0.85);
+  color: #f5f7fb;
+  border-radius: 14px;
+  padding: 14px 16px;
+}
+
+button {
+  border: 0;
+  border-radius: 999px;
+  padding: 13px 18px;
+  font-weight: 700;
+  background: linear-gradient(135deg, #74e0b8 0%, #1fb67a 100%);
+  color: #04141a;
+}
+
+.error {
+  color: #ffb7b7;
+}
+
+.status {
+  display: grid;
+  gap: 18px;
+}
+
+.status-row,
+.details {
+  display: flex;
+  justify-content: space-between;
+  gap: 16px;
+  flex-wrap: wrap;
+}
+
+.details div {
+  display: grid;
+  gap: 6px;
+}
+
+.details span {
+  color: #9db0cf;
+}
+
+.resource-list {
+  margin: 0;
+  padding-left: 18px;
+}