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

This reverts commit d59b59a7a7.

services/frontend/src/main.tsx

@@ -0,0 +1,19 @@
+import React from "react";
+import ReactDOM from "react-dom/client";
+import App from "./App";
+import { ToastProvider } from "./shared/ui";
+import "./styles.css";
+
+const root = document.getElementById("root");
+
+if (!root) {
+  throw new Error("Root element not found");
+}
+
+ReactDOM.createRoot(root).render(
+  <React.StrictMode>
+    <ToastProvider>
+      <App />
+    </ToastProvider>
+  </React.StrictMode>,
+);