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/state/app/modules/timetable/bloc/timetable_state.g.dart

@@ -6,56 +6,74 @@ part of 'timetable_state.dart';
 // JsonSerializableGenerator
 // **************************************************************************
 
-_TimetableState _$TimetableStateFromJson(Map<String, dynamic> json) =>
-    _TimetableState(
-      weekCache:
-          (json['weekCache'] as Map<String, dynamic>?)?.map(
+_TimetableState _$TimetableStateFromJson(
+  Map<String, dynamic> json,
+) => $checkedCreate('_TimetableState', json, ($checkedConvert) {
+  final val = _TimetableState(
+    weekCache: $checkedConvert(
+      'weekCache',
+      (v) =>
+          (v as Map<String, dynamic>?)?.map(
             (k, e) => MapEntry(
               k,
               TimetableGetWeekResponse.fromJson(e as Map<String, dynamic>),
             ),
           ) ??
           const <String, TimetableGetWeekResponse>{},
-      rooms: json['rooms'] == null
+    ),
+    rooms: $checkedConvert(
+      'rooms',
+      (v) => v == null
           ? null
-          : TimetableGetRoomsResponse.fromJson(
-              json['rooms'] as Map<String, dynamic>,
-            ),
-      subjects: json['subjects'] == null
+          : TimetableGetRoomsResponse.fromJson(v as Map<String, dynamic>),
+    ),
+    subjects: $checkedConvert(
+      'subjects',
+      (v) => v == null
           ? null
-          : TimetableGetSubjectsResponse.fromJson(
-              json['subjects'] as Map<String, dynamic>,
-            ),
-      schoolHolidays: json['schoolHolidays'] == null
+          : TimetableGetSubjectsResponse.fromJson(v as Map<String, dynamic>),
+    ),
+    schoolHolidays: $checkedConvert(
+      'schoolHolidays',
+      (v) => v == null
           ? null
-          : TimetableGetHolidaysResponse.fromJson(
-              json['schoolHolidays'] as Map<String, dynamic>,
-            ),
-      schoolyear: json['schoolyear'] == null
+          : TimetableGetHolidaysResponse.fromJson(v as Map<String, dynamic>),
+    ),
+    schoolyear: $checkedConvert(
+      'schoolyear',
+      (v) => v == null
           ? null
-          : TimetableGetSchoolyearResponse.fromJson(
-              json['schoolyear'] as Map<String, dynamic>,
-            ),
-      timegrid: json['timegrid'] == null
+          : TimetableGetSchoolyearResponse.fromJson(v as Map<String, dynamic>),
+    ),
+    timegrid: $checkedConvert(
+      'timegrid',
+      (v) => v == null
           ? null
-          : TimetableGetTimegridResponse.fromJson(
-              json['timegrid'] as Map<String, dynamic>,
-            ),
-      customEvents: json['customEvents'] == null
+          : TimetableGetTimegridResponse.fromJson(v as Map<String, dynamic>),
+    ),
+    customEvents: $checkedConvert(
+      'customEvents',
+      (v) => v == null
           ? null
-          : GetCustomTimetableEventResponse.fromJson(
-              json['customEvents'] as Map<String, dynamic>,
-            ),
-      startDate: DateTime.parse(json['startDate'] as String),
-      endDate: DateTime.parse(json['endDate'] as String),
-      dataVersion: (json['dataVersion'] as num?)?.toInt() ?? 0,
-      accessibleStartDate: json['accessibleStartDate'] == null
-          ? null
-          : DateTime.parse(json['accessibleStartDate'] as String),
-      accessibleEndDate: json['accessibleEndDate'] == null
-          ? null
-          : DateTime.parse(json['accessibleEndDate'] as String),
-    );
+          : GetCustomTimetableEventResponse.fromJson(v as Map<String, dynamic>),
+    ),
+    startDate: $checkedConvert('startDate', (v) => DateTime.parse(v as String)),
+    endDate: $checkedConvert('endDate', (v) => DateTime.parse(v as String)),
+    dataVersion: $checkedConvert(
+      'dataVersion',
+      (v) => (v as num?)?.toInt() ?? 0,
+    ),
+    accessibleStartDate: $checkedConvert(
+      'accessibleStartDate',
+      (v) => v == null ? null : DateTime.parse(v as String),
+    ),
+    accessibleEndDate: $checkedConvert(
+      'accessibleEndDate',
+      (v) => v == null ? null : DateTime.parse(v as String),
+    ),
+  );
+  return val;
+});
 
 Map<String, dynamic> _$TimetableStateToJson(_TimetableState instance) =>
     <String, dynamic>{