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/holidays/bloc/holidays_state.g.dart

@@ -7,13 +7,19 @@ part of 'holidays_state.dart';
 // **************************************************************************
 
 _HolidaysState _$HolidaysStateFromJson(Map<String, dynamic> json) =>
-    _HolidaysState(
-      showPastHolidays: json['showPastHolidays'] as bool,
-      showDisclaimer: json['showDisclaimer'] as bool,
-      holidays: (json['holidays'] as List<dynamic>)
-          .map((e) => McHoliday.fromJson(e as Map<String, dynamic>))
-          .toList(),
-    );
+    $checkedCreate('_HolidaysState', json, ($checkedConvert) {
+      final val = _HolidaysState(
+        showPastHolidays: $checkedConvert('showPastHolidays', (v) => v as bool),
+        showDisclaimer: $checkedConvert('showDisclaimer', (v) => v as bool),
+        holidays: $checkedConvert(
+          'holidays',
+          (v) => (v as List<dynamic>)
+              .map((e) => McHoliday.fromJson(e as Map<String, dynamic>))
+              .toList(),
+        ),
+      );
+      return val;
+    });
 
 Map<String, dynamic> _$HolidaysStateToJson(_HolidaysState instance) =>
     <String, dynamic>{