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/vite.config.ts

@@ -1,25 +0,0 @@
-import react from "@vitejs/plugin-react";
-import { defineConfig } from "vite";
-
-export default defineConfig({
-  plugins: [react()],
-  build: {
-    rolldownOptions: {
-      checks: {
-        pluginTimings: false,
-      },
-    },
-  },
-  server: {
-    middlewareMode: false,
-  },
-  preview: {
-    port: 3000,
-    host: true,
-    allowedHosts: [
-      "imphnen.asepharyana.my.id",
-      "imphnen.asepharyana.tech",
-      "imphnen.asepharyana.web.id",
-    ],
-  },
-});