feat: add useCloseServiceOnBack hook to intercept back navigation and trigger Flutter service closure

src/app/questions-list/page.tsx

@@ -30,8 +30,10 @@ import { useI18n } from "@/translations/provider";
 import { toFrontendSlug } from "@/data/section-slug-map";
 import SectionsRequest from "./sections-request";
 import { getStoredAge, getLocalSectionProgress } from "@/components/questions/progress-helper";
+import { useCloseServiceOnBack } from "@/hooks/use-close-service-on-back";
 
 export default function QuestionsListPage() {
+  useCloseServiceOnBack();
   const { dictionary: t, locale } = useI18n();
   const router = useRouter();
   const { data: profile } = useMarriageProfileQuery();

src/hooks/use-close-service-on-back.ts

@@ -0,0 +1,41 @@
+"use client";
+
+import { useEffect } from "react";
+
+/**
+ * Hook to intercept browser/hardware back button (popstate) and trigger
+ * Flutter's `close_service` action when running inside Flutter WebView.
+ */
+export function useCloseServiceOnBack(enabled: boolean = true) {
+  useEffect(() => {
+    if (!enabled || typeof window === "undefined") {
+      return;
+    }
+
+    const app = (window as any).HabibApp;
+    if (!app?.postMessage) {
+      return;
+    }
+
+    // Push a dummy history state so hardware back triggers popstate instead of navigating away
+    window.history.pushState({ closeOnBack: true }, "", window.location.href);
+
+    const handlePopState = () => {
+      if ((window as any).HabibApp?.postMessage) {
+        // Keep the state pinned in webview and notify Flutter to close the webview
+        window.history.pushState({ closeOnBack: true }, "", window.location.href);
+        (window as any).HabibApp.postMessage(
+          JSON.stringify({ action: "close_service" }),
+        );
+      }
+    };
+
+    window.addEventListener("popstate", handlePopState);
+
+    return () => {
+      window.removeEventListener("popstate", handlePopState);
+    };
+  }, [enabled]);
+}
+
+export default useCloseServiceOnBack;