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/create_poll/create_poll_params.g.dart

@@ -7,14 +7,18 @@ part of 'create_poll_params.dart';
 // **************************************************************************
 
 CreatePollParams _$CreatePollParamsFromJson(Map<String, dynamic> json) =>
-    CreatePollParams(
-      question: json['question'] as String,
-      options: (json['options'] as List<dynamic>)
-          .map((e) => e as String)
-          .toList(),
-      resultMode: (json['resultMode'] as num).toInt(),
-      maxVotes: (json['maxVotes'] as num).toInt(),
-    );
+    $checkedCreate('CreatePollParams', json, ($checkedConvert) {
+      final val = CreatePollParams(
+        question: $checkedConvert('question', (v) => v as String),
+        options: $checkedConvert(
+          'options',
+          (v) => (v as List<dynamic>).map((e) => e as String).toList(),
+        ),
+        resultMode: $checkedConvert('resultMode', (v) => (v as num).toInt()),
+        maxVotes: $checkedConvert('maxVotes', (v) => (v as num).toInt()),
+      );
+      return val;
+    });
 
 Map<String, dynamic> _$CreatePollParamsToJson(CreatePollParams instance) =>
     <String, dynamic>{