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/api/marianumcloud/app_password/delete_app_password.dart

@@ -2,19 +2,24 @@ import 'package:http/http.dart' as http;
 
 import '../nextcloud_ocs.dart';
 
-/// Revokes the current app password server-side via
-/// `DELETE /ocs/v2.php/core/apppassword`. Best-effort: the shared OCS headers
-/// authenticate with the app password itself (it revokes the credential it was
-/// made with) and the result is ignored — logout clears local state regardless.
+/// Revokes an app password server-side via
+/// `DELETE /ocs/v2.php/core/apppassword`. The endpoint revokes the credential
+/// the request authenticates WITH — by default the shared OCS headers (general
+/// app password); pass [authorizationHeader] to revoke another one (the Talk
+/// app password). Best-effort: the result is ignored — logout clears local
+/// state regardless.
 class DeleteAppPassword {
   final http.Client _client;
 
   DeleteAppPassword({http.Client? client}) : _client = client ?? http.Client();
 
-  Future<void> run() async {
+  Future<void> run({String? authorizationHeader}) async {
     await _client.delete(
       NextcloudOcs.uri('core/apppassword'),
-      headers: NextcloudOcs.headers(),
+      headers: {
+        ...NextcloudOcs.headers(),
+        'Authorization': ?authorizationHeader,
+      },
     );
   }
 }

lib/api/marianumconnect/queries/push_device_register/push_device_register.dart

@@ -19,6 +19,7 @@ class PushDeviceRegister {
     required String userPublicKey,
     required String pushToken,
     required String platform,
+    required String registrationType,
     String? appVersion,
   }) async {
     try {
@@ -30,6 +31,9 @@ class PushDeviceRegister {
           'userPublicKey': userPublicKey,
           'pushToken': pushToken,
           'platform': platform,
+          // 'general' | 'talk' — the backend derives the NC hash comparison
+          // value from it (general = sha512(token), talk = sha512(token+'#talk')).
+          'registrationType': registrationType,
           'appVersion': ?appVersion,
         },
       );