fixed stale state after logout and replayed or lost share intents

lib/push/push_actions.dart

@@ -60,6 +60,10 @@ class PushActions {
     // auth header, the Talk POST never happens and the RemoteInput spinner
     // runs forever.
     DartPluginRegistrant.ensureInitialized();
+    // The action engine lives as long as the process: without a reload a
+    // reply would be sent with the account that was signed in when the
+    // engine first started.
+    await AccountData().reloadFromStorage();
 
     _plog(
       'action=${response.actionId} payload=${response.payload} '

lib/push/push_message_handler.dart

@@ -4,6 +4,7 @@ import 'package:crypton/crypton.dart';
 import 'package:firebase_messaging/firebase_messaging.dart';
 
 import '../background/widget_background_task.dart';
+import '../model/account_data.dart';
 import '../notification/notification_service.dart';
 import 'chat_thread_store.dart';
 import 'nid_store.dart';
@@ -54,6 +55,8 @@ PushKind classifyPush(Map<String, dynamic> data) {
 /// "must be annotated"), so a plain function is the reliable form.
 @pragma('vm:entry-point')
 Future<void> pushOnBackgroundMessage(RemoteMessage message) async {
+  // This engine outlives sign-outs and logins in the app.
+  await AccountData().reloadFromStorage();
   await NotificationService().initializeNotifications();
   await PushRenderer.ensureChannels();
   await PushMessageHandler().handle(message);

lib/push/push_registration.dart

@@ -107,6 +107,7 @@ class PushRegistration {
   /// fire-and-forget (and simply ignore the result).
   Future<bool> register() async {
     if (DemoMode.active) return false;
+    final epoch = AccountData().sessionEpoch;
     final String? fcmToken;
     try {
       fcmToken = await FirebaseMessaging.instance.getToken();
@@ -159,6 +160,7 @@ class PushRegistration {
         fcmToken: fcmToken,
         pems: pems,
         appVersion: appVersion,
+        epoch: epoch,
       );
       allOk = allOk && ok;
     }
@@ -170,6 +172,7 @@ class PushRegistration {
     required String fcmToken,
     required PushKeypairPems pems,
     required String? appVersion,
+    required int epoch,
   }) async {
     try {
       final proxyServer = currentProxyServer;
@@ -185,6 +188,11 @@ class PushRegistration {
         userAgent: isTalk ? _talkUserAgent : null,
       );
 
+      // Signed out while registering: persisting or announcing this
+      // registration would keep delivering the previous account's pushes,
+      // and logoutCleanup already ran so nothing would unregister it.
+      if (!AccountData().isCurrentSession(epoch)) return false;
+
       await _store.save(
         type: type,
         deviceIdentifier: registration.deviceIdentifier,