hardened API decoding against server fields the models did not expect

The Talk room list crashed for a new account because the server omits
lastMessage for rooms without a visible message and the model required it.
Beyond that single field, a review of the Talk models against the OpenAPI
spec of the installed version (23.0.8) found the same crash class in several
places: closed enums over open server values (inCall bitmask, rich-object
types, actor and message types), a deleted parent sent as {id, deleted},
and the autocomplete status arriving as an object.

- json_serializable `checked: true`: decode errors now name class and field
- lists (rooms, messages, participants, autocomplete) decode per entry;
  a malformed entry is skipped and reported via ClientErrorReporter
- unknownEnumValue fallbacks for all response enums of Talk and breakers
- lastMessage nullable; inCall as bitmask; deleted parent placeholder;
  autocomplete status object/string; fixed shareWithDisplayNameUnique key
- GetRoomParams no longer sends null query parameters

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01HrepDTL4qDe35TuS29sLW3

lib/api/marianumcloud/talk/get_participants/get_participants_response.dart

@@ -1,11 +1,13 @@
 import 'package:json_annotation/json_annotation.dart';
 
 import '../../../api_response.dart';
+import '../../../json_lenient.dart';
 
 part 'get_participants_response.g.dart';
 
 @JsonSerializable(explicitToJson: true)
 class GetParticipantsResponse extends ApiResponse {
+  @JsonKey(fromJson: _participantsFromJson)
   Set<GetParticipantsResponseObject> data;
 
   GetParticipantsResponse(this.data);
@@ -15,15 +17,25 @@ class GetParticipantsResponse extends ApiResponse {
   Map<String, dynamic> toJson() => _$GetParticipantsResponseToJson(this);
 }
 
+Set<GetParticipantsResponseObject> _participantsFromJson(Object? raw) =>
+    decodeSetLenient(
+      raw,
+      GetParticipantsResponseObject.fromJson,
+      what: 'participant',
+    );
+
 @JsonSerializable(explicitToJson: true)
 class GetParticipantsResponseObject {
   int attendeeId;
   String actorType;
   String actorId;
   String displayName;
+  @JsonKey(unknownEnumValue: GetParticipantsResponseObjectParticipantType.user)
   GetParticipantsResponseObjectParticipantType participantType;
   int lastPing;
-  GetParticipantsResponseObjectParticipantsInCallFlags inCall;
+
+  /// Bitmask: 1 = in call, 2 = with audio, 4 = with video, 8 = via phone.
+  int inCall;
   int permissions;
   int attendeePermissions;
   String? sessionId;
@@ -54,6 +66,11 @@ class GetParticipantsResponseObject {
   factory GetParticipantsResponseObject.fromJson(Map<String, dynamic> json) =>
       _$GetParticipantsResponseObjectFromJson(json);
   Map<String, dynamic> toJson() => _$GetParticipantsResponseObjectToJson(this);
+
+  bool get isInCall => inCall & 1 != 0;
+  bool get inCallWithAudio => inCall & 2 != 0;
+  bool get inCallWithVideo => inCall & 4 != 0;
+  bool get inCallViaPhone => inCall & 8 != 0;
 }
 
 enum GetParticipantsResponseObjectParticipantType {
@@ -73,16 +90,3 @@ enum GetParticipantsResponseObjectParticipantType {
   const GetParticipantsResponseObjectParticipantType(this.prettyName);
   final String prettyName;
 }
-
-enum GetParticipantsResponseObjectParticipantsInCallFlags {
-  @JsonValue(0)
-  disconnected,
-  @JsonValue(1)
-  inCall,
-  @JsonValue(2)
-  providesAudio,
-  @JsonValue(3)
-  providesVideo,
-  @JsonValue(4)
-  usesSipDialIn,
-}

lib/api/marianumcloud/talk/get_participants/get_participants_response.g.dart

@@ -8,19 +8,18 @@ part of 'get_participants_response.dart';
 
 GetParticipantsResponse _$GetParticipantsResponseFromJson(
   Map<String, dynamic> json,
-) =>
-    GetParticipantsResponse(
-        (json['data'] as List<dynamic>)
-            .map(
-              (e) => GetParticipantsResponseObject.fromJson(
-                e as Map<String, dynamic>,
-              ),
-            )
-            .toSet(),
-      )
-      ..headers = (json['headers'] as Map<String, dynamic>?)?.map(
-        (k, e) => MapEntry(k, e as String),
-      );
+) => $checkedCreate('GetParticipantsResponse', json, ($checkedConvert) {
+  final val = GetParticipantsResponse(
+    $checkedConvert('data', (v) => _participantsFromJson(v)),
+  );
+  $checkedConvert(
+    'headers',
+    (v) => val.headers = (v as Map<String, dynamic>?)?.map(
+      (k, e) => MapEntry(k, e as String),
+    ),
+  );
+  return val;
+});
 
 Map<String, dynamic> _$GetParticipantsResponseToJson(
   GetParticipantsResponse instance,
@@ -31,29 +30,36 @@ Map<String, dynamic> _$GetParticipantsResponseToJson(
 
 GetParticipantsResponseObject _$GetParticipantsResponseObjectFromJson(
   Map<String, dynamic> json,
-) => GetParticipantsResponseObject(
-  (json['attendeeId'] as num).toInt(),
-  json['actorType'] as String,
-  json['actorId'] as String,
-  json['displayName'] as String,
-  $enumDecode(
-    _$GetParticipantsResponseObjectParticipantTypeEnumMap,
-    json['participantType'],
-  ),
-  (json['lastPing'] as num).toInt(),
-  $enumDecode(
-    _$GetParticipantsResponseObjectParticipantsInCallFlagsEnumMap,
-    json['inCall'],
-  ),
-  (json['permissions'] as num).toInt(),
-  (json['attendeePermissions'] as num).toInt(),
-  json['sessionId'] as String?,
-  (json['sessionIds'] as List<dynamic>).map((e) => e as String).toList(),
-  json['status'] as String?,
-  json['statusIcon'] as String?,
-  json['statusMessage'] as String?,
-  json['roomToken'] as String?,
-);
+) => $checkedCreate('GetParticipantsResponseObject', json, ($checkedConvert) {
+  final val = GetParticipantsResponseObject(
+    $checkedConvert('attendeeId', (v) => (v as num).toInt()),
+    $checkedConvert('actorType', (v) => v as String),
+    $checkedConvert('actorId', (v) => v as String),
+    $checkedConvert('displayName', (v) => v as String),
+    $checkedConvert(
+      'participantType',
+      (v) => $enumDecode(
+        _$GetParticipantsResponseObjectParticipantTypeEnumMap,
+        v,
+        unknownValue: GetParticipantsResponseObjectParticipantType.user,
+      ),
+    ),
+    $checkedConvert('lastPing', (v) => (v as num).toInt()),
+    $checkedConvert('inCall', (v) => (v as num).toInt()),
+    $checkedConvert('permissions', (v) => (v as num).toInt()),
+    $checkedConvert('attendeePermissions', (v) => (v as num).toInt()),
+    $checkedConvert('sessionId', (v) => v as String?),
+    $checkedConvert(
+      'sessionIds',
+      (v) => (v as List<dynamic>).map((e) => e as String).toList(),
+    ),
+    $checkedConvert('status', (v) => v as String?),
+    $checkedConvert('statusIcon', (v) => v as String?),
+    $checkedConvert('statusMessage', (v) => v as String?),
+    $checkedConvert('roomToken', (v) => v as String?),
+  );
+  return val;
+});
 
 Map<String, dynamic> _$GetParticipantsResponseObjectToJson(
   GetParticipantsResponseObject instance,
@@ -66,9 +72,7 @@ Map<String, dynamic> _$GetParticipantsResponseObjectToJson(
       _$GetParticipantsResponseObjectParticipantTypeEnumMap[instance
           .participantType]!,
   'lastPing': instance.lastPing,
-  'inCall':
-      _$GetParticipantsResponseObjectParticipantsInCallFlagsEnumMap[instance
-          .inCall]!,
+  'inCall': instance.inCall,
   'permissions': instance.permissions,
   'attendeePermissions': instance.attendeePermissions,
   'sessionId': instance.sessionId,
@@ -87,11 +91,3 @@ const _$GetParticipantsResponseObjectParticipantTypeEnumMap = {
   GetParticipantsResponseObjectParticipantType.userFollowingPublicLink: 5,
   GetParticipantsResponseObjectParticipantType.guestWithModeratorPermissions: 6,
 };
-
-const _$GetParticipantsResponseObjectParticipantsInCallFlagsEnumMap = {
-  GetParticipantsResponseObjectParticipantsInCallFlags.disconnected: 0,
-  GetParticipantsResponseObjectParticipantsInCallFlags.inCall: 1,
-  GetParticipantsResponseObjectParticipantsInCallFlags.providesAudio: 2,
-  GetParticipantsResponseObjectParticipantsInCallFlags.providesVideo: 3,
-  GetParticipantsResponseObjectParticipantsInCallFlags.usesSipDialIn: 4,
-};