fix: Drop invalid SetNull and SetDefault test models (#165)

Co-authored-by: Cursor Agent <cursoragent@cursor.com>
Co-authored-by: Marcelo Mendonça Soares <marcelomendoncasoares@users.noreply.github.com>

example/offline_sync_demo/lib/src/snapshot.dart

@@ -319,7 +319,7 @@ IconData iconForTable(String table, {required bool hidden}) {
     'town' => Icons.map,
     'organization' => Icons.apartment,
     'company' => Icons.business,
-    'restrict_child' || 'required_set_null_child' => Icons.link,
+    'restrict_child' => Icons.link,
     'unique' || 'unique_uuid' || 'unique_composite' => Icons.key,
     'types' => Icons.data_object,
     _ when table.startsWith('fk_chain') => Icons.account_tree,

example/offline_sync_demo/lib/src/table_ops.dart

@@ -160,14 +160,6 @@ final Map<String, TableOps> demoTableOps = {
       create: (id, label, foreignKeys) =>
           RestrictChild(id: id, name: label, parentId: foreignKeys['parentId']),
     ),
-    _ops<RequiredSetNullChild>(
-      canCreateRoot: false,
-      create: (id, label, foreignKeys) {
-        final parentId = foreignKeys['parentId'];
-        if (parentId == null) return null;
-        return RequiredSetNullChild(id: id, name: label, parentId: parentId);
-      },
-    ),
     _ops<Unique>(
       create: (id, label, foreignKeys) => Unique(id: id, name: label),
     ),

example/offline_sync_demo/pubspec.yaml

@@ -16,7 +16,7 @@ dependencies:
   http: ^1.5.0
   path: ^1.9.1
   path_provider: ^2.1.5
-  serverpod_database: ^4.0.0
+  serverpod_database: '>=4.0.4 <4.1.0'
   serverpod_offline_sync_client:
     path: ../../packages/serverpod_offline_sync_client
   serverpod_offline_sync_test_client: