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/autocomplete/autocomplete_response.dart

@@ -1,5 +1,6 @@
 import 'package:json_annotation/json_annotation.dart';
 
+import '../../json_lenient.dart';
 import '../files_sharing/queries/share/share.dart';
 
 part 'autocomplete_response.g.dart';
@@ -14,6 +15,7 @@ int shareTypeFromSource(String? source) {
 
 @JsonSerializable(explicitToJson: true)
 class AutocompleteResponse {
+  @JsonKey(fromJson: _entriesFromJson)
   List<AutocompleteResponseObject> data;
 
   AutocompleteResponse(this.data);
@@ -23,15 +25,31 @@ class AutocompleteResponse {
   Map<String, dynamic> toJson() => _$AutocompleteResponseToJson(this);
 }
 
+List<AutocompleteResponseObject> _entriesFromJson(Object? raw) =>
+    decodeListLenient(
+      raw,
+      AutocompleteResponseObject.fromJson,
+      what: 'autocomplete entry',
+    );
+
+/// The server sends a user-status object for users that have one and an empty
+/// string otherwise; only the status string itself is kept.
+String? _statusFromJson(Object? raw) => switch (raw) {
+  Map<String, dynamic> status => status['status']?.toString(),
+  String status when status.isNotEmpty => status,
+  _ => null,
+};
+
 @JsonSerializable()
 class AutocompleteResponseObject {
   String id;
   String label;
   String? icon;
   String? source;
+  @JsonKey(fromJson: _statusFromJson)
   String? status;
   String? subline;
-  String? shareWithDisplayNameUniqe;
+  String? shareWithDisplayNameUnique;
 
   AutocompleteResponseObject(
     this.id,
@@ -40,7 +58,7 @@ class AutocompleteResponseObject {
     this.source,
     this.status,
     this.subline,
-    this.shareWithDisplayNameUniqe,
+    this.shareWithDisplayNameUnique,
   );
 
   factory AutocompleteResponseObject.fromJson(Map<String, dynamic> json) =>