fixed bug that prevents sending messages if reply was triggered in a different chat

lib/api/errors/talk_exception.dart

@@ -4,16 +4,22 @@ import 'app_exception.dart';
 class TalkException extends AppException {
   final TalkError source;
 
-  TalkException(this.source)
+  TalkException(this.source, {String? technicalDetails})
     : super(
         userMessage: _mapMessage(source),
         technicalDetails:
+            technicalDetails ??
             'Talk ${source.status} (${source.code}): ${source.message}',
         allowRetry: source.code >= 500,
       );
 
   static String _mapMessage(TalkError e) {
     switch (e.code) {
+      case 400:
+        return 'Talk hat diese Anfrage abgelehnt. Bitte lade den Chat neu und '
+            'versuche es erneut.';
+      case 413:
+        return 'Diese Nachricht ist zu lang.';
       case 401:
         return 'Bitte melde dich erneut an, um auf Talk zuzugreifen.';
       case 403:

lib/api/marianumcloud/talk/talk_api.dart

@@ -6,8 +6,10 @@ import '../../api_params.dart';
 import '../../api_response.dart';
 import '../../errors/network_exception.dart';
 import '../../errors/parse_exception.dart';
+import '../../errors/talk_exception.dart';
 import '../../http_errors.dart';
 import '../nextcloud_ocs.dart';
+import 'talk_error.dart';
 
 abstract class TalkApi<T extends ApiResponse?> {
   String path;
@@ -49,6 +51,16 @@ abstract class TalkApi<T extends ApiResponse?> {
       // logs surface the cause instead of just the bare status code.
       final detail = httpErrorDetail('Talk $endpoint', data.body, status);
       log(detail);
+      // Talk's own codes need their own wording: a 400/412/413 here is a
+      // rejected request, not a struggling server, and "try again later"
+      // would send the user in circles. 401/403/404 keep the shared mapping
+      // so the auth handling stays in one place.
+      if (status == 400 || status == 412 || status == 413 || status == 429) {
+        throw TalkException(
+          TalkError('failure', status, ''),
+          technicalDetails: detail,
+        );
+      }
       throwForStatus(status, detail);
     }