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/send_message/send_message_params.g.dart

@@ -7,10 +7,13 @@ part of 'send_message_params.dart';
 // **************************************************************************
 
 SendMessageParams _$SendMessageParamsFromJson(Map<String, dynamic> json) =>
-    SendMessageParams(
-      json['message'] as String,
-      replyTo: json['replyTo'] as String?,
-    );
+    $checkedCreate('SendMessageParams', json, ($checkedConvert) {
+      final val = SendMessageParams(
+        $checkedConvert('message', (v) => v as String),
+        replyTo: $checkedConvert('replyTo', (v) => v as String?),
+      );
+      return val;
+    });
 
 Map<String, dynamic> _$SendMessageParamsToJson(SendMessageParams instance) =>
     <String, dynamic>{