Add TanStack Router, TanStack Query, Directus client, entity types

frontend/src/routes/index.tsx

@@ -0,0 +1,10 @@
+import { createFileRoute } from '@tanstack/react-router'
+
+export const Route = createFileRoute('/')({
+  component: () => (
+    <div className="p-8">
+      <h1 className="text-3xl font-bold">Home</h1>
+      <p className="text-muted-foreground">Routing placeholder — CMS page will render here.</p>
+    </div>
+  ),
+})