Improve jsify and dartify Type

lib/src/base/contactor/utils/utils.dart

@@ -1,12 +1,12 @@
 import 'dart:js_interop';
 
 /// Returns Dart representation from JS Object.
-dynamic dartify(dynamic object) {
+Object? dartify(dynamic object) {
   // Convert JSObject to Dart equivalents directly
   // Cannot be done with Dart 3.2 constraints
   // ignore: invalid_runtime_check_with_js_interop_types
   if (object is! JSObject) {
-    return object;
+    return object as Object?;
   }
 
   final jsObject = object;
@@ -16,11 +16,12 @@ dynamic dartify(dynamic object) {
   return convertNested(dartObject);
 }
 
-dynamic convertNested(dynamic object) {
+/// Convert nested Map or List.
+Object? convertNested(Object? object) {
   if (object is List) {
     return object.map(convertNested).toList();
   } else if (object is Map) {
-    var map = <dynamic, dynamic>{};
+    final map = <dynamic, dynamic>{};
     object.forEach((key, value) {
       map[key] = convertNested(value);
     });
@@ -34,15 +35,17 @@ dynamic convertNested(dynamic object) {
 /// Returns the JS implementation from Dart Object.
 JSAny? jsify(Object? dartObject) {
   if (dartObject == null) {
-    return dartObject?.jsify();
+    return dartObject.jsify();
   }
 
   if (dartObject is List) {
     return dartObject.map(jsify).toList().toJS;
   }
 
   if (dartObject is Map) {
-    return dartObject.map((key, value) => MapEntry(key, jsify(value))).jsify();
+    return dartObject
+        .map((key, value) => MapEntry(jsify(key), jsify(value)))
+        .jsify();
   }
 
   if (dartObject is JSAny Function()) {

lib/src/isolate_manager_controller/web.dart

@@ -63,7 +63,7 @@ class _IsolateManagerWorkerController<R, P>
 
   _IsolateManagerWorkerController(this.self) {
     self.onmessage = (MessageEvent event) {
-      _streamController.sink.add(dartify(event.data));
+      _streamController.sink.add(dartify(event.data) as P);
     }.toJS;
   }