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/marianumconnect/queries/get_ticker_nav/get_ticker_nav_response.g.dart

@@ -7,15 +7,26 @@ part of 'get_ticker_nav_response.dart';
 // **************************************************************************
 
 TickerNavResponse _$TickerNavResponseFromJson(Map<String, dynamic> json) =>
-    TickerNavResponse(
-      schemaVersion: (json['schemaVersion'] as num?)?.toInt() ?? 1,
-      navHash: json['navHash'] as String? ?? '',
-      sections:
-          (json['sections'] as List<dynamic>?)
-              ?.map((e) => TickerNavSection.fromJson(e as Map<String, dynamic>))
-              .toList() ??
-          [],
-    );
+    $checkedCreate('TickerNavResponse', json, ($checkedConvert) {
+      final val = TickerNavResponse(
+        schemaVersion: $checkedConvert(
+          'schemaVersion',
+          (v) => (v as num?)?.toInt() ?? 1,
+        ),
+        navHash: $checkedConvert('navHash', (v) => v as String? ?? ''),
+        sections: $checkedConvert(
+          'sections',
+          (v) =>
+              (v as List<dynamic>?)
+                  ?.map(
+                    (e) => TickerNavSection.fromJson(e as Map<String, dynamic>),
+                  )
+                  .toList() ??
+              [],
+        ),
+      );
+      return val;
+    });
 
 Map<String, dynamic> _$TickerNavResponseToJson(TickerNavResponse instance) =>
     <String, dynamic>{
@@ -25,14 +36,22 @@ Map<String, dynamic> _$TickerNavResponseToJson(TickerNavResponse instance) =>
     };
 
 TickerNavSection _$TickerNavSectionFromJson(Map<String, dynamic> json) =>
-    TickerNavSection(
-      title: json['title'] as String? ?? '',
-      pages:
-          (json['pages'] as List<dynamic>?)
-              ?.map((e) => TickerNavPage.fromJson(e as Map<String, dynamic>))
-              .toList() ??
-          [],
-    );
+    $checkedCreate('TickerNavSection', json, ($checkedConvert) {
+      final val = TickerNavSection(
+        title: $checkedConvert('title', (v) => v as String? ?? ''),
+        pages: $checkedConvert(
+          'pages',
+          (v) =>
+              (v as List<dynamic>?)
+                  ?.map(
+                    (e) => TickerNavPage.fromJson(e as Map<String, dynamic>),
+                  )
+                  .toList() ??
+              [],
+        ),
+      );
+      return val;
+    });
 
 Map<String, dynamic> _$TickerNavSectionToJson(TickerNavSection instance) =>
     <String, dynamic>{
@@ -41,15 +60,21 @@ Map<String, dynamic> _$TickerNavSectionToJson(TickerNavSection instance) =>
     };
 
 TickerNavPage _$TickerNavPageFromJson(Map<String, dynamic> json) =>
-    TickerNavPage(
-      title: json['title'] as String? ?? '',
-      slug: json['slug'] as String? ?? '',
-      kind: json['kind'] as String? ?? 'CONTENT',
-      hash: json['hash'] as String?,
-      externalUrl: json['externalUrl'] as String?,
-      externalUrlNewTab: json['externalUrlNewTab'] as bool?,
-      fileUrl: json['fileUrl'] as String?,
-    );
+    $checkedCreate('TickerNavPage', json, ($checkedConvert) {
+      final val = TickerNavPage(
+        title: $checkedConvert('title', (v) => v as String? ?? ''),
+        slug: $checkedConvert('slug', (v) => v as String? ?? ''),
+        kind: $checkedConvert('kind', (v) => v as String? ?? 'CONTENT'),
+        hash: $checkedConvert('hash', (v) => v as String?),
+        externalUrl: $checkedConvert('externalUrl', (v) => v as String?),
+        externalUrlNewTab: $checkedConvert(
+          'externalUrlNewTab',
+          (v) => v as bool?,
+        ),
+        fileUrl: $checkedConvert('fileUrl', (v) => v as String?),
+      );
+      return val;
+    });
 
 Map<String, dynamic> _$TickerNavPageToJson(TickerNavPage instance) =>
     <String, dynamic>{