docs: reorganize documentation with i18n and Swagger API reference

- Add per-submodule docs structure (server-core, dashboard-ui, device-agent)
- Restructure VitePress with i18n support (Indonesian default + English)
- Add Swagger API reference pages with Swagger UI CDN embed
- Create merge.js script for combining sidebar manifests
- Integrate docs build into Docker (update.sh + nginx volume mount)
- Add documentation section to root README

apps/docs/.vitepress/config.mts

@@ -1,22 +1,50 @@
 import { defineConfig } from 'vitepress'
 
+// Sidebar manifests from submodules
+import serverCoreSidebar from '../../server-core/docs/sidebar.json'
+import dashboardSidebar from '../../dashboard-ui/docs/sidebar.json'
+import agentSidebar from '../../device-agent/docs/sidebar.json'
+
 export default defineConfig({
-  title: 'NexusGuard Docs',
-  description: 'Enterprise Zero-Trust SD-WAN Documentation',
+  title: 'NexusGuard',
+  description: 'Enterprise Zero-Trust SD-WAN Suite',
+  base: '/docs/',
   cleanUrls: true,
-  themeConfig: {
-    sidebar: [
-      {
-        text: 'Guides',
-        items: [
-          { text: 'Sign In', link: '/guides/sign-in' },
-          { text: 'Access Remote Server', link: '/guides/access-remote-server' },
-          { text: 'Add WireGuard Configuration', link: '/guides/add-wireguard-configuration' },
-          { text: 'Peers', link: '/guides/peers' },
-          { text: 'Email Service', link: '/guides/email-service' },
-          { text: 'WebHooks', link: '/guides/webhooks' },
-        ]
-      }
-    ]
-  }
+
+  locales: {
+    root: {
+      label: 'Bahasa Indonesia',
+      lang: 'id',
+      themeConfig: {
+        sidebar: [
+          serverCoreSidebar,
+          dashboardSidebar,
+          agentSidebar,
+        ],
+        nav: [
+          { text: 'Beranda', link: '/' },
+          { text: 'Panduan', link: '/guides/' },
+          { text: 'API', link: '/api/' },
+          { text: 'GitHub', link: 'https://git.datadunia.com/nexusguard/Nexus-Guard-Suite' },
+        ],
+      },
+    },
+    en: {
+      label: 'English',
+      lang: 'en',
+      themeConfig: {
+        sidebar: [
+          serverCoreSidebar,
+          dashboardSidebar,
+          agentSidebar,
+        ],
+        nav: [
+          { text: 'Home', link: '/en/' },
+          { text: 'Guides', link: '/en/guides/' },
+          { text: 'API', link: '/en/api/' },
+          { text: 'GitHub', link: 'https://git.datadunia.com/nexusguard/Nexus-Guard-Suite' },
+        ],
+      },
+    },
+  },
 })