TS7 upgrade + write to TS over JS

frontend/src/main.tsx

@@ -0,0 +1,12 @@
+import { StrictMode } from "react";
+import { createRoot } from "react-dom/client";
+import App from "./App";
+
+const root = document.getElementById("root");
+if (!root) throw new Error("Root element not found");
+
+createRoot(root).render(
+    <StrictMode>
+        <App />
+    </StrictMode>,
+);