init

frontend/src/main.tsx

@@ -0,0 +1,16 @@
+import React from "react";
+import ReactDOM from "react-dom/client";
+import { HashRouter } from "react-router-dom";
+
+import App from "./App";
+
+// HashRouter, not BrowserRouter: the same bundle is loaded from http:// by the
+// web app and from file:// by the packaged desktop app, and only the hash
+// router works in both without a server rewrite.
+ReactDOM.createRoot(document.getElementById("root")!).render(
+  <React.StrictMode>
+    <HashRouter>
+      <App />
+    </HashRouter>
+  </React.StrictMode>,
+);