feat: migrate frontend to Astro + expand AI moderation + backend admin/runtime config

Frontend:
- migrate from Vite to Astro (astro.config.mjs, pages/, layouts/)
- add admin panel, settings page, command palette, error boundary
- refactor App.tsx, MascotChatbot, Sidebar, Header, DashboardLayout
- update API client, WebSocket, auth, dashboard features

Backend:
- add admin module and config routes
- refactor middlewares, Redis connection, WebSocket server/bridge
- add runtime config loader

Discord Gateway:
- refactor AI moderation: circuit breaker, concurrency limiter, fallback processor
- add media analysis client, Seaxng search, user profile learner
- add new drizzle migration

Shared:
- extend database schema, add new config fields

services/frontend/astro.config.mjs

@@ -0,0 +1,45 @@
+import { defineConfig } from "astro/config";
+import react from "@astrojs/react";
+
+// ─────────────────────────────────────────────────────────────
+// BETE – Astro Configuration
+// Tailwind v4 ditangani via PostCSS (postcss.config.js)
+// ─────────────────────────────────────────────────────────────
+export default defineConfig({
+  integrations: [react()],
+
+  output: "static",
+
+  // Dev server
+  server: {
+    host: "0.0.0.0",
+    port: 3000,
+  },
+
+  // Preview
+  preview: {
+    host: true,
+    port: 3000,
+    allowedHosts: [
+      "imphnen.asepharyana.my.id",
+      "imphnen.asepharyana.tech",
+      "imphnen.asepharyana.web.id",
+    ],
+  },
+
+  // Vite config
+  vite: {
+    server: {
+      allowedHosts: [
+        "imphnen.asepharyana.my.id",
+        "imphnen.asepharyana.tech",
+        "imphnen.asepharyana.web.id",
+      ],
+      watch: {
+        // Penting: Astro punya public/ dir sendiri, jangan bentrok
+        ignored: ["!**/node_modules/**"],
+      },
+    },
+    // PostCSS otomatis terdeteksi dari root project
+  },
+});