implemented dual Nextcloud push registration with separate general and talk apptypes to ensure reliable Talk notification delivery; introduced stacked MessagingStyle notifications for chat threads with support for circular conversation avatars and disk caching

lib/push/push_message_handler.dart

@@ -4,6 +4,7 @@ import 'package:crypton/crypton.dart';
 import 'package:firebase_messaging/firebase_messaging.dart';
 
 import '../notification/notification_service.dart';
+import 'chat_thread_store.dart';
 import 'nid_store.dart';
 import 'push_decryptor.dart';
 import 'push_keypair.dart';
@@ -34,6 +35,17 @@ PushKind classifyPush(Map<String, dynamic> data) {
   return PushKind.unknown;
 }
 
+/// FCM background isolate entry point. Must be a TOP-LEVEL function with the
+/// entry-point pragma: AOT builds cannot invoke static class members from
+/// native code unless the class itself is annotated too (DartVM error
+/// "must be annotated"), so a plain function is the reliable form.
+@pragma('vm:entry-point')
+Future<void> pushOnBackgroundMessage(RemoteMessage message) async {
+  await NotificationService().initializeNotifications();
+  await PushRenderer.ensureChannels();
+  await PushMessageHandler().handle(message);
+}
+
 /// Verifies, decrypts, and renders incoming push messages. Delete-pushes cancel
 /// the matching tray notification via [NidStore]. Works both in the FCM
 /// background isolate and the foreground.
@@ -42,25 +54,19 @@ class PushMessageHandler {
   final PushRegistrationStore _registrationStore;
   final PushRenderer _renderer;
   final NidStore _nidStore;
+  final ChatThreadStore _threadStore;
 
   PushMessageHandler({
     PushKeypair? keypair,
     PushRegistrationStore? registrationStore,
     PushRenderer? renderer,
     NidStore? nidStore,
+    ChatThreadStore? threadStore,
   }) : _keypair = keypair ?? const PushKeypair(),
        _registrationStore = registrationStore ?? const PushRegistrationStore(),
        _renderer = renderer ?? PushRenderer(),
-       _nidStore = nidStore ?? NidStore();
-
-  /// Background isolate entry point registered with
-  /// `FirebaseMessaging.onBackgroundMessage`.
-  @pragma('vm:entry-point')
-  static Future<void> onBackgroundMessage(RemoteMessage message) async {
-    await NotificationService().initializeNotifications();
-    await PushRenderer.ensureChannels();
-    await PushMessageHandler().handle(message);
-  }
+       _nidStore = nidStore ?? NidStore(),
+       _threadStore = threadStore ?? ChatThreadStore();
 
   /// Processes [message]. In the foreground, pass [foreground] true and
   /// [openChatToken] so a message for the currently open chat is suppressed
@@ -157,6 +163,7 @@ class PushMessageHandler {
         await _cancel(entry);
       }
       await _nidStore.clear();
+      await _threadStore.clearAll();
       return;
     }
     final nids = <int>[
@@ -165,7 +172,20 @@ class PushMessageHandler {
     ];
     for (final nid in nids) {
       final entry = await _nidStore.get(nid);
-      if (entry != null) await _cancel(entry);
+      final chatToken = entry?.chatToken;
+      if (chatToken != null && chatToken.isNotEmpty) {
+        // Stacked chat notification: drop only this message from the thread.
+        // Remaining messages re-render WITHOUT alerting again; the last one
+        // going away cancels the whole card.
+        final remaining = await _threadStore.removeNid(chatToken, nid);
+        if (remaining.isEmpty) {
+          await _cancel(entry!);
+        } else {
+          await _renderer.renderTalkThread(chatToken, remaining, alert: false);
+        }
+      } else if (entry != null) {
+        await _cancel(entry);
+      }
       await _nidStore.delete(nid);
     }
   }