feat: prompt user on window close

Author: brettkolodny

src/client/App.tsx

@@ -43,9 +43,17 @@ import {
 } from "lucide-react";
 import { type FC, useEffect, useMemo, useRef, useState } from "react";
 import { useDebouncedValue } from "./hooks/debounce";
-import { useSearchParams } from "react-router";
+import { useBeforeUnload, useSearchParams } from "react-router";
 
 export const App = () => {
+useBeforeUnload(
+(e) => {
+e.preventDefault();
+return true;
+},
+{ capture: true },
+);
+
 const [wasmLoadState, setWasmLoadingState] = useState<WasmLoadState>(() => {
 if (window.go_preview) {
 return "loaded";